Abdominal pain is discomfort or pain felt anywhere between the chest and groin. It ranges from mild and self-limiting (gas, indigestion) to severe and life-threatening (appendicitis, perforated ulcer, ectopic pregnancy). The location, character, and associated symptoms help guide diagnosis. Sudden severe abdominal pain is a medical emergency.
Japan & United States
Medical Glossary
260 healthcare terms covering Japan's and the United States' medical systems — each with a plain-English definition and translations into Japanese, Chinese, Korean, Portuguese, Spanish, Filipino, Thai, and Vietnamese. Filter by region (Japan or US) and by category. US terms are also available at the US section →
A
The Affordable Care Act (ACA), signed into law in 2010, is the major US health reform legislation that expanded insurance coverage through multiple mechanisms: the Health Insurance Marketplace with income-based subsidies, Medicaid expansion in participating states, requirements for coverage of pre-existing conditions, prohibition on lifetime and annual benefit limits, extension of dependent coverage to age 26, and requirements for coverage of essential health benefits and preventive services without cost-sharing. The ACA significantly reduced the uninsured rate in the US.
A certificate obtained in advance from the health insurer that caps the amount a patient pays at the hospital counter for a single month, preventing the need to pay large sums upfront and then seek reimbursement. Without this certificate, patients must pay the full copayment amount and later file for a high-cost medical expense rebate. It is particularly important for planned surgeries or hospital admissions.
Allergy tests identify specific substances (allergens) that trigger immune reactions. Methods include blood tests measuring specific IgE antibodies (RAST), skin prick tests, and patch tests for contact dermatitis. In Japan, allergy tests are commonly used to identify triggers for allergic rhinitis (especially cedar pollen), food allergies, and atopic dermatitis, conditions that are very prevalent in Japan.
In a medical emergency in Japan, dial 119 to request an ambulance. Paramedics will arrive and transport you to the nearest appropriate hospital. Ambulance transport itself is free at point of use, though you will be billed separately for hospital treatment. Dispatchers may have limited English, so knowing basic Japanese emergency phrases or having a translation app ready is strongly recommended when calling for help.
Amniocentesis is a prenatal diagnostic procedure in which a small sample of amniotic fluid is withdrawn via a needle inserted through the abdomen to test for chromosomal abnormalities or genetic conditions. In Japan, it is offered to higher-risk pregnant women, typically those over 35 or with abnormal screening results. The procedure is usually performed between 15 and 18 weeks of pregnancy. Genetic counseling (iden kaunseringu) is strongly recommended before undergoing amniocentesis in Japan.
Anaphylaxis is a severe, potentially fatal allergic reaction occurring within minutes of exposure to an allergen such as food, insect stings, or medication. Symptoms include hives, swelling of the throat, breathing difficulty, and dangerously low blood pressure. Those with known severe allergies should carry an epinephrine auto-injector (EpiPen) and a Japanese-language allergy card. Call 119 immediately if anaphylaxis is suspected, even after using an auto-injector.
Anesthesiology (麻酔科, masui-ka) is the specialty responsible for administering anesthesia (sedation and pain management) during surgical procedures, and monitoring patients' vital signs throughout operations. Anesthesiologists also manage acute and chronic pain, and provide intensive care. Pre-operative evaluations ensure anesthesia is safe for the individual patient.
An annual wellness visit is a preventive healthcare appointment with a primary care provider focused on health maintenance rather than treatment of an existing condition. Under the ACA, covered plans must provide these visits at no cost when in-network. For Medicare beneficiaries, the Annual Wellness Visit (AWV) reviews health risk factors, updates a personalized prevention plan, and screens for cognitive impairment — distinct from the Welcome to Medicare visit for new enrollees. Combining a wellness visit with treatment of an active problem may result in a separate copay for the treatment portion.
A medicine that neutralizes excess stomach acid to relieve heartburn, indigestion, and acid reflux. OTC antacids in Japan often contain aluminum hydroxide, magnesium hydroxide, or calcium carbonate, sold under brand names like Gascon or Mylanta. Proton-pump inhibitors (PPIs) such as omeprazole are available by prescription for chronic conditions like GERD and peptic ulcers.
A class of medication used to treat bacterial infections by killing or inhibiting the growth of bacteria. Antibiotics are not effective against viruses, so they are not prescribed for common colds or influenza. In Japan, antibiotics require a doctor's prescription and are dispensed at a pharmacy. Completing the full prescribed course is essential to prevent antibiotic-resistant bacteria from developing.
A medication that reduces the frequency of loose or watery stools by slowing intestinal motility or absorbing excess fluid. Loperamide (Imodium) is widely available OTC in Japan for non-infectious diarrhea. If diarrhea is caused by infection, antidiarrheal agents may be withheld by physicians to allow the body to expel pathogens naturally. Oral rehydration salts should accompany treatment to prevent dehydration.
A medicine used to treat infections caused by fungi, such as athlete's foot (mizumushi), ringworm, oral thrush, or vaginal candidiasis. Topical antifungals like clotrimazole and terbinafine are available over the counter in Japan for skin conditions. Systemic oral antifungals such as fluconazole require a prescription. Athlete's foot products are especially popular in Japan and widely stocked at drugstores.
A drug that blocks histamine receptors to relieve allergic symptoms such as sneezing, runny nose, itching, and hives. In Japan, both first-generation (drowsy) and second-generation (non-drowsy) antihistamines are available. Many popular brands like Allegra (fexofenadine) and Claritin are sold over the counter at pharmacies, while stronger formulations may require a prescription. These are widely used for hay fever (kafun-shō), which affects a large portion of the Japanese population.
A medicine that reduces fever by acting on the hypothalamus to lower the body's temperature set point. The most common antipyretic available in Japan is acetaminophen (paracetamol), sold as Calonal or Tylenol. Aspirin is generally avoided for children due to the risk of Reye's syndrome. Mild formulations are available over the counter, while higher-dose preparations require a prescription.
A medication that inhibits the replication of viruses within the body. In Japan, common antivirals include oseltamivir (Tamiflu) and baloxavir (Xofluza) for influenza, acyclovir for herpes infections, and nirmatrelvir/ritonavir (Paxlovid) for COVID-19. Most antivirals require a physician's prescription and are most effective when started within 48 hours of symptom onset.
Anxiety is a feeling of worry, nervousness, or unease about anticipated events or uncertain outcomes. When persistent and impairing daily function, it constitutes an anxiety disorder. Physical symptoms include rapid heartbeat, sweating, trembling, and shortness of breath. Japan's mental health services have expanded; seeking help is increasingly normalized though stigma remains in some settings.
The appendix is a small, finger-shaped pouch of tissue attached to the large intestine in the lower right abdomen. Its function is not fully understood. Appendicitis — inflammation of the appendix — is a surgical emergency requiring prompt removal. Symptoms include sudden sharp pain in the lower right abdomen, fever, and nausea.
The Advanced Premium Tax Credit (APTC) is a federal subsidy that helps eligible individuals and families pay for health insurance purchased through the Marketplace. Eligibility is based on household income as a percentage of the federal poverty level and filing status. The credit can be applied in advance to monthly premiums, reducing what you pay each month, or claimed as a credit at tax filing. Income changes during the year should be reported promptly to avoid repayment at tax time.
B
Back pain is pain felt in the lower, middle, or upper back. Lower back pain (腰痛, yōtsū) is one of the most common complaints in Japan and worldwide, often caused by muscle strain, herniated disc, or spinal stenosis. Most acute back pain resolves within a few weeks with rest and pain management. Persistent or severe back pain, especially with leg weakness or bladder problems, requires prompt evaluation.
Balance billing occurs when an out-of-network provider bills a patient for the difference between their charge and the amount the insurer pays, in addition to any required cost-sharing. For example, if a provider charges $1,000 and the insurer pays $600, the provider may attempt to bill the patient the remaining $400 'balance.' The No Surprises Act (effective 2022) bans balance billing in most emergency situations and for certain non-emergency services by out-of-network providers at in-network facilities.
See EOB — Explanation of Benefits. The benefits summary, or EOB, is the document your insurer sends after processing a claim. It is not a bill but shows what was charged, what the insurer paid, any negotiated discounts, and your remaining financial responsibility. Reviewing the EOB against your provider's bill is essential for catching errors. Discrepancies should be reported to both the insurer and the provider. EOBs also show how much of your deductible and out-of-pocket maximum you have used for the year.
A biopsy involves removing a small sample of tissue from the body for laboratory examination under a microscope. It is the definitive method for diagnosing cancer and many other conditions. Biopsies can be taken from skin, lymph nodes, organs (liver, kidney), or tissues detected on imaging. Results typically take several days to weeks to process in Japanese pathology laboratories.
The Birth Lump-Sum Grant (出産育児一時金, shussan ikuji ichiji kin) is a one-time payment made to insured individuals who give birth in Japan. As of 2023, the standard amount is 500,000 yen per baby. It can be applied directly toward hospital delivery costs or paid to the insured after birth. The grant is available to all enrolled insured persons, including foreign nationals, for each child born.
A birth notification (shussei todoke) is the legal document that must be filed with the local municipal office within 14 days of a child's birth in Japan, regardless of the parents' nationality. Failure to file can affect the child's legal status and eligibility for residency registration. Foreign residents must also report the birth to their consulate or embassy. Filing triggers the family registry (koseki) entry for Japanese nationals and the residency record for foreign families.
The bladder is a hollow muscular organ in the pelvis that stores urine produced by the kidneys until it is expelled through urination. Common conditions include cystitis (urinary tract infection, UTI), urinary incontinence, and bladder cancer. UTIs are very common, especially in women, and are treated quickly at urology or internal medicine clinics in Japan.
Bleeding refers to the escape of blood from damaged blood vessels. External bleeding (visible wounds) or internal bleeding (blood in stool, urine, vomit, or coughed up) requires medical evaluation. Rectal bleeding is common and can range from hemorrhoids to colorectal cancer. Uncontrollable external bleeding is a medical emergency; apply firm pressure while awaiting emergency services.
Blood pressure measurement records the force of blood against arterial walls, expressed as systolic pressure (心収縮期, maximum) over diastolic pressure (拡張期, minimum), measured in mmHg. Normal blood pressure is below 120/80 mmHg. Hypertension (高血圧, kōketsuatsu) is defined as 140/90 mmHg or above. It is a standard procedure performed at virtually every Japanese clinic visit.
A blood test involves drawing a small sample of blood, usually from a vein in the arm, to analyze its components and chemical markers. It can assess red and white blood cell counts, organ function (liver, kidney, thyroid), blood sugar, cholesterol, inflammation markers, and infection indicators. Blood tests are the most frequently ordered diagnostic procedure in Japanese medical care.
A blood transfusion is a medical procedure in which donated blood or blood components (red blood cells, plasma, platelets) are transferred into a patient's bloodstream intravenously. It is used to treat severe anemia, significant blood loss from surgery or trauma, and clotting disorders. Japan's blood supply is managed by the Japanese Red Cross Society and is considered very safe with strict screening protocols.
Blood vessels are the network of tubes — arteries, veins, and capillaries — through which blood circulates. Arteries carry oxygenated blood from the heart; veins return deoxygenated blood. Conditions such as atherosclerosis (narrowing due to plaque buildup) and hypertension are leading causes of cardiovascular disease and are monitored closely in Japan's health checkups.
Bones form the skeletal framework of the body, providing structure, protecting organs, anchoring muscles, and storing calcium. The adult human body has 206 bones. Fractures are common after falls; Japan's aging population has a high rate of osteoporosis-related fractures, particularly of the hip and wrist.
The brain is the central organ of the nervous system, housed within the skull. It controls thought, memory, emotion, sensory processing, motor function, and regulation of bodily processes. Sudden severe headache, confusion, or one-sided weakness can indicate a stroke (脳卒中, nōsocchū) — a medical emergency requiring immediate attention.
A brand-name drug is a medication sold under a proprietary trade name by the pharmaceutical company that developed it and holds the patent. Brand-name drugs are typically placed in higher formulary tiers with higher cost-sharing. Once the patent expires, other manufacturers can produce FDA-approved generic versions. Some conditions may require brand-name drugs when generics are not therapeutically interchangeable; insurers may require prior authorization or step therapy before covering brand-name options.
Breastfeeding is the practice of feeding an infant with milk produced by the mother. In Japan, breastfeeding is widely encouraged by medical professionals and government health policy. Many hospitals provide lactation consultants to support new mothers from the first day. Baby-friendly hospital designations indicate facilities committed to breastfeeding promotion. Nursing rooms (junyūshitsu) are available in shopping centers, train stations, and many public spaces, making breastfeeding relatively manageable while out in public.
A bruise (contusion) is discoloration of the skin caused by bleeding under the skin after trauma, appearing blue-purple initially and fading to yellow-green as it heals. Spontaneous bruising without injury, or bruising that spreads rapidly, can indicate clotting disorders, liver disease, or blood cancers and warrants blood tests to assess platelet count and clotting factors.
A burn is tissue damage caused by heat, chemicals, electricity, or radiation. Burns are classified by depth: superficial (first degree), partial thickness (second degree), or full thickness (third degree). For minor burns, apply cool running water for at least 10 minutes. For severe or large burns, call 119 immediately. Never apply ice or butter, which worsen tissue damage. Serious burns are treated at specialized burn units in major hospitals across Japan.
C
Cardiac arrest occurs when the heart suddenly stops beating, cutting off blood flow to the brain and vital organs. Call 119 immediately and begin CPR without delay. Japan has an extensive network of publicly accessible AEDs located in train stations, shopping centers, and public buildings. Japanese emergency dispatchers can guide callers through CPR steps by telephone. Brain damage can occur within minutes, making immediate bystander response absolutely critical.
Cardiology (循環器科, junkanki-ka) is the specialty concerned with diseases of the heart and blood vessels. It manages conditions such as coronary artery disease, heart failure, arrhythmias, hypertension, and valvular disease. Cardiologists use ECGs, echocardiograms, stress tests, and cardiac catheterization for diagnosis. Japan has excellent cardiac care with low rates of coronary artery disease compared to Western countries.
The Centers for Disease Control and Prevention (CDC) is the leading federal public health agency in the United States, operating under HHS. The CDC conducts research on disease prevention, monitors health trends, responds to outbreaks and public health emergencies, and provides health information to the public. It develops vaccination schedules and clinical guidelines used by healthcare providers nationwide. The CDC's website (cdc.gov) is an authoritative source of health information including vaccine recommendations, travel health advisories, and disease statistics.
A cesarean section is a surgical procedure in which a baby is delivered through incisions made in the mother's abdomen and uterus. In Japan, the cesarean rate is approximately 25 to 30 percent and rising. Planned cesareans are scheduled in advance, while emergency cesareans may be required due to complications during labor. When medically indicated, the procedure is covered by national health insurance. Hospital stays after a cesarean in Japan are typically longer than in Western countries.
Charity care is free or reduced-cost medical care provided by hospitals to patients who cannot afford to pay. Non-profit hospitals are required by federal law to have written financial assistance policies (FAPs) and must provide charity care as a condition of their tax-exempt status. Eligibility is typically income-based, often using a percentage of the federal poverty level. Patients must apply — charity care is not automatic — and may need to provide income documentation. Applications can often be submitted after receiving care.
Chest pain is discomfort or pain in the chest area that can range from a dull ache to sharp stabbing sensations. While musculoskeletal causes are common, chest pain can signal serious cardiac events such as angina or myocardial infarction (heart attack). Sudden crushing chest pain, especially with shortness of breath, sweating, or arm pain, requires immediate emergency care.
A chest X-ray uses low-dose radiation to create images of the heart, lungs, ribs, and diaphragm. It is used to diagnose pneumonia, tuberculosis, heart enlargement, pleural effusion, and lung tumors. In Japan, a chest X-ray is a standard component of annual health checkups and is required for certain long-term visa applications as tuberculosis screening.
A municipal government program that reduces or eliminates the out-of-pocket medical costs for children up to a locally defined age limit, often up to junior high or high school. Coverage varies significantly by municipality; some areas cover all costs with no copayment, while others require a small fee per visit. Foreign resident children enrolled in national health insurance are generally eligible if registered at the ward office.
Chills are episodes of shivering or feeling cold, often accompanied by goosebumps and teeth chattering, even when the surrounding environment is warm. Chills frequently precede or accompany fever and are caused by the body raising its internal temperature in response to infection. They may also occur with blood infections (sepsis), malaria, or severe bacterial illness.
CHIP (Children's Health Insurance Program) provides low-cost health coverage to children in families that earn too much to qualify for Medicaid but cannot afford private insurance. Coverage includes doctor visits, immunizations, hospital care, dental, and vision. Some states extend CHIP coverage to pregnant women. CHIP is jointly funded by federal and state governments and administered by states; income eligibility thresholds vary by state. Most children pay no premiums, though some states charge modest premiums.
Choking occurs when a foreign object blocks the airway, preventing breathing. Signs include inability to speak, a high-pitched breathing sound, blue-tinged lips, or a silent cough. For conscious adults and children, use the Heimlich maneuver. For infants, use back blows and chest thrusts. Call 119 if the object cannot be dislodged. Japanese public spaces and restaurants commonly post first-aid choking charts, and AEDs in public areas often include first-aid instruction guides.
A cholesterol test, also called a lipid panel, measures the levels of total cholesterol, LDL (bad) cholesterol, HDL (good) cholesterol, and triglycerides in your blood. You are usually required to fast for 9 to 12 hours beforehand. Results help doctors assess your risk of cardiovascular disease and stroke, and guide recommendations about diet, physical activity, or cholesterol-lowering medication such as statins.
A clinical trial is a research study conducted on human participants to evaluate the safety and effectiveness of medical interventions such as new drugs, devices, or procedures. Trials are conducted in phases: Phase I tests safety, Phase II tests efficacy, Phase III compares to existing treatments, and Phase IV monitors long-term effects after approval. Participation is voluntary and requires informed consent. The ACA requires most insurance plans to cover routine costs associated with approved clinical trial participation.
The Centers for Medicare & Medicaid Services (CMS) is the federal agency within HHS responsible for administering Medicare, Medicaid, CHIP, and the ACA Marketplace. CMS sets payment rates, quality standards, and coverage policies for federal health programs. It oversees the HealthCare.gov marketplace and processes over 1 billion claims per year. CMS also regulates clinical laboratories under CLIA, nursing homes, and home health agencies. It publishes data on hospital quality and cost transparency.
COBRA (Consolidated Omnibus Budget Reconciliation Act) allows workers and their families to continue employer-sponsored group health coverage for a limited period after leaving a job or experiencing other qualifying events such as reduced hours, divorce, or death of the covered employee. COBRA coverage is identical to the former employer plan but the individual typically pays the full premium plus an administrative fee, making it significantly more expensive than when employed. Coverage continues for up to 18 months in most cases.
The COBRA election period is the 60-day window after losing employer-sponsored coverage (or receiving the COBRA election notice) during which an eligible employee or dependent can choose to continue their group health coverage under COBRA. The election deadline is strictly enforced; missing it forfeits the right to COBRA. Coverage, once elected, is retroactive to the date of loss of coverage, meaning a person can wait until they have a medical expense before enrolling and still receive retroactive coverage — though they must pay all retroactive premiums.
Coinsurance is the percentage of costs you pay for a covered service after you have met your deductible. For example, if your plan has 20% coinsurance, your insurer pays 80% and you pay 20% of the allowed amount. Coinsurance applies to most in-network services and continues until you reach your out-of-pocket maximum, after which the insurer covers 100% of covered costs for the rest of the plan year.
Colonoscopy is a procedure in which a flexible camera is inserted through the rectum to examine the entire large intestine (colon). It is used to screen for and remove polyps before they become colorectal cancer, and to investigate bleeding, diarrhea, and unexplained abdominal pain. Japan's annual fecal occult blood test (便潜血検査, ben senketsukensa) screens for colon cancer and positive results lead to colonoscopy.
A compounding pharmacy prepares customized medications to meet the specific needs of individual patients when commercially available drugs do not fit their requirements. Examples include adjusting drug strength, changing the dosage form (liquid instead of tablet), removing an allergen, or combining medications. Compounding pharmacies are regulated by state pharmacy boards and, in some cases, the FDA. Insurance typically does not cover compounded medications unless prior authorization is obtained. Quality and sterility standards vary among compounding pharmacies.
Constipation is having fewer than three bowel movements per week, with stools that are hard, dry, and difficult to pass. Causes include low-fiber diet, inadequate fluid intake, lack of exercise, medications (especially opioids), and underlying conditions such as hypothyroidism or colorectal cancer. Constipation is a very common complaint in Japan, especially among women and the elderly.
A medication subject to strict government regulation due to its potential for abuse, dependence, or harm. Japan classifies controlled substances under the Narcotics and Psychotropics Control Act. Categories include narcotics (opioids), psychotropics (benzodiazepines, stimulants), and designated substances. Foreign residents must obtain Japanese prescriptions; bringing controlled substances into Japan from abroad requires advance government approval and documentation. Violations carry severe legal penalties.
A copayment is a fixed dollar amount you pay for a covered healthcare service, such as a doctor visit or prescription, at the time of service. Copays are set by your insurance plan and do not count toward your deductible in some plans. Common copays include $20–$40 for a primary care visit and $50–$100 for a specialist. After meeting your deductible, copays often remain in effect until you reach your out-of-pocket maximum.
The copayment (自己負担, jiko futan) is the percentage of medical costs you pay out of pocket after insurance covers the remainder. In Japan, the standard rate for working-age adults is 30% of the total bill. Children up to junior high school and elderly patients aged 70 and above pay a reduced rate of 10 to 20% depending on income. The copayment applies at clinics, hospitals, and pharmacies.
A cough is a reflex action that clears the throat and airways of irritants, mucus, and foreign particles. Acute coughs are usually caused by infections (cold, flu, COVID-19). Chronic coughs lasting more than three weeks may indicate asthma, allergies, or gastroesophageal reflux disease (GERD). In Japan, tuberculosis must be considered in persistent cough, and free screening is available for long-term residents.
A CT (computed tomography) scan uses multiple X-ray images taken at different angles and processed by a computer to create detailed cross-sectional images of the body. It is used to diagnose conditions in the brain, chest, abdomen, and pelvis including tumors, bleeding, and vascular disease. CT scans with contrast dye provide enhanced detail of blood vessels and soft tissues.
D
A deductible is the amount you pay out of pocket for covered health services before your insurance begins to share costs. For example, with a $1,500 deductible, you pay the first $1,500 of covered services each year before coinsurance or lower copays kick in. Preventive care is typically covered before the deductible under the ACA. Family plans may have separate individual and family deductibles. High-deductible health plans (HDHPs) pair with HSAs for tax savings.
Dehydration occurs when the body loses more fluid than it takes in, disrupting normal bodily functions. Japan's hot and humid summers make dehydration a common cause of hospitalization, particularly among elderly people and children. Mild dehydration can be managed with oral rehydration solutions available at pharmacies. Severe dehydration requiring IV fluids must be treated at a hospital or clinic. Seek medical care if symptoms include extreme thirst, dizziness, rapid heartbeat, or confusion.
Dentistry (歯科, shika) covers the diagnosis, prevention, and treatment of conditions affecting teeth, gums, and oral structures. Services include fillings, extractions, root canals, crowns, periodontal care, and orthodontics. Japan's national health insurance covers basic dental treatments; cosmetic procedures (teeth whitening, implants) are typically not covered and require out-of-pocket payment.
Dermatology (皮膚科, hifuka) is the specialty concerned with diseases of the skin, hair, and nails. Common conditions treated include atopic dermatitis, psoriasis, acne, urticaria (hives), fungal infections, and skin cancer. Japanese dermatology clinics are plentiful, often do not require referrals, and have short wait times compared to other specialties.
Dialysis is a medical procedure that filters waste products and excess fluid from the blood when the kidneys can no longer do so adequately. Hemodialysis uses a machine with an external filter, while peritoneal dialysis uses the lining of the abdomen. Patients with chronic kidney failure typically need hemodialysis three times per week, with each session lasting three to five hours at a designated dialysis clinic or hospital.
Diarrhea is the passage of loose, watery stools more than three times per day. It is commonly caused by viral gastroenteritis, bacterial food poisoning, stress, or certain medications including antibiotics. Diarrhea can lead to dehydration, especially in the elderly and infants. Persistent diarrhea lasting more than two weeks, or diarrhea containing blood, should be evaluated by a physician.
Financial support paid to insured individuals who develop a qualifying physical or mental disability while enrolled in national pension or employee insurance. The benefit level depends on the severity of disability (Grade 1 or Grade 2) and is assessed by a government panel. Foreign residents enrolled in Japan's pension system for the required period are eligible to apply.
Dizziness is a broad term describing sensations of lightheadedness, unsteadiness, or the false sense that surroundings are spinning (vertigo). Common causes include inner ear disorders, low blood pressure when standing (orthostatic hypotension), anemia, dehydration, and neurological conditions. Dizziness with sudden weakness on one side of the body or slurred speech may indicate stroke.
Durable Medical Equipment (DME) refers to medical devices prescribed by a physician for repeated use in the home to treat a medical condition. Examples include wheelchairs, walkers, hospital beds, oxygen equipment, CPAP machines, blood glucose monitors, and prosthetics. Medicare Part B covers DME when it is medically necessary and prescribed by a doctor. Private insurance DME coverage varies; prior authorization is commonly required. DME must be purchased from a Medicare-approved supplier for Medicare coverage to apply.
Drowning is respiratory impairment from liquid submersion that can cause brain damage within minutes. In Japan, incidents spike in summer near rivers, beaches, and pools. If someone is rescued from water and appears unresponsive, call 119 and begin CPR if trained. Japan's coastal and riverine rescue services are operated by local fire departments. Always swim in supervised areas and wear a life jacket on boats, as warning signs at waterways may only be posted in Japanese.
A drug formulary is a list of prescription medications covered by a health insurance plan. Formularies are organized into tiers, typically ranging from Tier 1 (generic, lowest cost) to Tier 4 or 5 (specialty drugs, highest cost). Drugs not on the formulary require an exception or prior authorization. Formularies change annually and sometimes mid-year; patients should verify their medications are covered before enrolling in a plan or filling a new prescription. Generic substitutes are often available for off-formulary drugs.
Dual-eligible individuals qualify for both Medicare and Medicaid. Medicare is the primary payer; Medicaid pays for costs Medicare does not cover, such as cost-sharing, long-term care, and additional benefits. Dual eligibles include elderly and disabled low-income individuals. They may be enrolled in Dual Eligible Special Needs Plans (D-SNPs) that coordinate both programs. About 12 million Americans are dual-eligible, and they often have complex medical needs. Navigating dual eligibility can be administratively challenging and may require assistance from a benefits counselor.
E
The ears are organs of hearing and balance, comprising the outer, middle, and inner ear. Common conditions include otitis media (middle ear infection), earwax buildup, and tinnitus. The inner ear also plays a role in balance; disorders such as benign paroxysmal positional vertigo (BPPV) cause dizziness and are commonly seen in Japanese ear clinics.
Liquid medication applied directly into the ear canal to treat conditions such as otitis externa (swimmer's ear), earwax softening, or minor bacterial or fungal ear infections. In Japan, ear drops containing antibiotics or antifungals are dispensed by prescription. Some OTC products for earwax softening exist, but most medicated ear drops require a physician's evaluation first. Tilt the head to allow drops to reach the canal and remain for the prescribed time.
An ECG (electrocardiogram, 心電図, shindenzu) records the electrical activity of the heart using electrodes placed on the chest, arms, and legs. It detects arrhythmias, myocardial infarction, conduction abnormalities, and chamber enlargement. The resting 12-lead ECG is a painless, 5-minute test included in many Japanese annual health checkups.
Emergency medicine (救急科, kyūkyū-ka) provides immediate care for acute illnesses and injuries that threaten life or require urgent treatment. In Japan, emergency care is provided at hospitals with an emergency room (救急外来, kyūkyū gairai). The emergency number is 119 for ambulance and fire services, and operators may have basic English support.
The emergency room (kyūkyū gairai) in Japan handles life-threatening and urgent medical conditions around the clock. Walk-in patients with minor complaints may face long waits or be redirected to an outpatient clinic. Staff at many facilities have limited English ability, especially at night. Bring your health insurance card, a list of current medications, and a translation card describing your condition to every emergency room visit.
The emergency room (ER), also called the emergency department (ED), provides immediate care for life-threatening or severe medical conditions including chest pain, stroke, severe breathing difficulty, serious injuries, and major bleeding. ER visits are among the most expensive healthcare encounters in the US. Insurers must cover emergency care at in-network cost-sharing levels even when the ER is out-of-network, under the No Surprises Act. Non-emergency visits to the ER often result in high bills and long wait times.
Employee Health Insurance (社会保険, Shakai Hoken) covers full-time employees and their eligible dependents at participating companies. Premiums are split between employer and employee and are automatically deducted from monthly salary. It generally offers lower out-of-pocket costs than National Health Insurance, bundles pension contributions, and extends dependent coverage to spouses and children who earn below a threshold.
Employer-sponsored insurance (ESI) is health coverage provided through a place of employment. Employers typically pay a portion of premiums and employees pay the rest through pre-tax payroll deductions. ESI is the most common source of health insurance in the US, covering about half the population. Employers with 50 or more full-time equivalent employees are required under the ACA to offer coverage meeting minimum value standards. Coverage typically extends to spouses and dependents. Losing employer-sponsored coverage triggers a Special Enrollment Period.
Upper gastrointestinal endoscopy (胃カメラ, i-kamera — literally 'stomach camera') involves passing a thin flexible camera through the mouth to visualize the esophagus, stomach, and duodenum. It is used to diagnose ulcers, gastritis, H. pylori infection, and stomach cancer. In Japan, gastroscopy is recommended from age 40 as stomach cancer screening due to high national incidence.
An epidural is regional anesthesia injected into the epidural space of the lower spine to reduce or eliminate pain during labor and delivery. In Japan, epidural analgesia is not universally available and is offered mainly at larger hospitals and specialized maternity clinics. If you want an epidural, confirm its availability and any additional cost with your chosen facility well before your due date, as it may not be covered by national health insurance and can add significant expense.
An EPO (Exclusive Provider Organization) combines features of HMO and PPO plans. Like an HMO, it typically does not cover out-of-network care (except emergencies), but like a PPO, it usually does not require referrals to see specialists. Members must use the plan's network of providers for all non-emergency care. EPOs often have premiums between HMO and PPO levels. They are increasingly common in ACA marketplace plans.
An Explanation of Benefits (EOB) is a document sent by your insurer after a medical claim is processed. It details the services billed, the amount the provider charged, what the insurer paid, any adjustments, and what you owe. An EOB is not a bill — it is a summary of how a claim was handled. Reviewing your EOB helps you catch billing errors, verify that claims were processed correctly, and understand your remaining deductible and out-of-pocket balance.
The eyes are the organs of sight, converting light into nerve signals sent to the brain. Common eye conditions include myopia (nearsightedness), conjunctivitis (pink eye), glaucoma, and cataracts. Japan has high rates of myopia, particularly in younger populations, and excellent ophthalmological services are widely available.
Liquid medication applied directly into the eye to treat conditions such as dry eye, allergic conjunctivitis, bacterial eye infections, or glaucoma. Japan has an extensive OTC eye drop market with popular brands like Rohto and Sante. Prescription eye drops are used for glaucoma (prostaglandin analogues, beta-blockers) and post-surgical care. Medicated eye drops should never be shared between users due to infection risk.
F
Fainting (syncope) is a temporary loss of consciousness caused by insufficient blood flow to the brain, usually resulting in a brief blackout and rapid recovery. Common causes include standing too quickly (vasovagal syncope), dehydration, cardiac arrhythmias, or severe pain. Fainting from a cardiac cause (arrhythmia) is more serious and requires evaluation with an ECG and heart monitoring.
Fatigue is persistent, overwhelming tiredness not relieved by rest. It differs from normal tiredness after exertion. Causes include anemia, thyroid dysfunction, diabetes, depression, sleep disorders, and viral illnesses such as Epstein-Barr. Chronic fatigue syndrome (慢性疲労症候群, mansei hirō shōkōgun) is a recognized diagnosis. Persistent unexplained fatigue warrants a blood test to investigate common causes.
Fever is an elevation of body temperature above the normal range (37°C / 98.6°F), typically defined as 38°C (100.4°F) or higher. It is usually a sign that the immune system is fighting an infection. Causes range from common colds and influenza to more serious bacterial infections. Sustained high fever or fever in infants requires prompt medical attention.
First aid is immediate basic medical care given to an injured or ill person before professional help arrives. In Japan, local fire departments offer free first aid training courses to residents. Public spaces widely stock AEDs for cardiac emergencies. Knowing how to call 119, describe your location in Japanese, and perform CPR or the Heimlich maneuver can be life-saving in the critical minutes before paramedics reach the scene.
A Federally Qualified Health Center (FQHC) is a community-based health clinic that receives federal grant funding under Section 330 of the Public Health Service Act. FQHCs must provide comprehensive primary care services to all patients regardless of insurance status or ability to pay, using a sliding fee scale. They serve medically underserved areas and populations and must meet federal performance standards. Services include primary care, mental health, dental, and pharmacy. FQHCs receive enhanced Medicare and Medicaid reimbursement rates.
A fracture is a broken bone caused by trauma, stress, or conditions such as osteoporosis. In Japan, fractures are treated in orthopedic departments (seikei geka). An X-ray confirms the break, and treatment may involve casting, splinting, or surgery depending on severity. Japan's national health insurance covers fracture treatment. If you suspect a fracture after an injury, immobilize the affected limb and seek medical attention promptly rather than attempting to move the injury.
A Flexible Spending Account (FSA) is an employer-sponsored pre-tax benefit account used to pay for eligible medical, dental, and vision expenses. Contributions reduce your taxable income. Unlike HSAs, FSAs generally follow a 'use it or lose it' rule — unspent funds may be forfeited at year-end, though some plans allow a grace period or limited rollover. FSAs can be used with any health plan type, not just HDHPs. Annual contribution limits are set by the IRS.
An FSA-eligible expense is a medical, dental, or vision cost that qualifies for payment using Flexible Spending Account funds. The IRS determines which expenses qualify. Eligible items include deductibles, copays, coinsurance, prescription medications, eyeglasses and contact lenses, dental work, medical equipment, and many over-the-counter medicines (without a prescription, thanks to the CARES Act). Non-eligible expenses include cosmetic procedures, gym memberships, and non-medical items. The FSA administrator or IRS Publication 502 provides the complete list.
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The gallbladder is a small pear-shaped organ beneath the liver that stores bile produced by the liver, releasing it into the small intestine to aid fat digestion. Gallstones (胆石, tanseki) are common and can cause severe right upper abdominal pain. Surgery to remove the gallbladder (cholecystectomy) is one of the most frequently performed procedures in Japanese hospitals.
Gastroenterology (消化器科, shōkaki-ka) specializes in diseases of the digestive system — esophagus, stomach, intestines, liver, pancreas, and gallbladder. Conditions managed include GERD, ulcers, hepatitis, inflammatory bowel disease, and colorectal cancer. Japan leads the world in gastric cancer incidence and endoscopic screening capabilities.
A pharmaceutical product that contains the same active ingredient, dosage, and formulation as a brand-name drug but is sold under its chemical name at a lower price after the original patent expires. Japan's government has actively promoted generic drug use to reduce healthcare costs, and pharmacists may substitute generics by default unless the prescriber or patient requests the brand name. Generics undergo bioequivalence testing and are considered therapeutically equivalent.
A generic drug is a medication that contains the same active ingredient, dosage form, strength, and route of administration as a brand-name drug, but is marketed under its chemical name after the brand's patent expires. Generic drugs are approved by the FDA and are therapeutically equivalent to their brand-name counterparts. They are significantly cheaper — often 80–85% less costly — and are placed in the lowest-cost formulary tiers. Requesting generics from your prescriber and pharmacist is a key way to reduce medication costs.
The glucose tolerance test (GTT) measures how efficiently your body processes sugar. You fast overnight, drink a standardized glucose solution, then have blood drawn at one- or two-hour intervals. Elevated blood glucose levels at these intervals indicate prediabetes, type 2 diabetes, or gestational diabetes. Results guide decisions on dietary changes, medication, and monitoring frequency for patients at risk of developing diabetes.
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A High-Deductible Health Plan (HDHP) has higher deductibles and lower premiums than traditional plans. The IRS sets minimum deductible thresholds annually that a plan must meet to qualify as an HDHP. The main benefit of an HDHP is eligibility to open a Health Savings Account (HSA), allowing pre-tax savings for medical expenses. HDHPs make sense for healthy individuals who rarely use healthcare and want to build HSA savings for future or retirement medical costs.
A headache is pain or discomfort in the head or upper neck. Tension headaches and migraines are the most common types. Warning signs for serious conditions include a sudden extremely severe headache (thunderclap headache), headache with fever and stiff neck (meningitis), or headache following head injury. These require immediate emergency evaluation.
An annual health checkup (健康診断, kenkō shindan) is a periodic medical examination designed to detect diseases early and monitor general health trends. In Japan, employers are legally required to provide checkups to full-time employees, and municipalities offer them to NHI members. A standard checkup includes body measurements, blood pressure, vision, hearing, and blood and urine tests for metabolic and organ function markers.
A voucher issued by municipalities or insurers that entitles the holder to receive a subsidized or free health screening at a participating clinic. These coupons may be issued for general annual checkups, cancer screenings, or pregnancy checkups. Foreign residents enrolled in national health insurance often receive these by post annually; unused coupons typically expire at the fiscal year end.
The health insurance card (健康保険証, kenkō hoken shō) is a physical card issued by your insurer that proves enrollment and allows access to reduced-cost medical care. You present it at hospitals, clinics, and pharmacies before each visit. It shows your name, insurance number, copayment rate, and insurer details. Losing it requires immediate reporting to your insurer or municipal office and requesting a replacement.
Health insurance enrollment (健康保険加入, kenkō hoken kanyū) is the process of registering as a member of Japan's public health insurance system. Working adults at qualifying companies are enrolled through their employer in Shakai Hoken; those without employer coverage must enroll in National Health Insurance at the municipal office. Enrollment is mandatory, and late registration can result in backdated premium payments for the entire uncovered period.
The Health Insurance Marketplace (also called the Exchange) is a platform created by the ACA where individuals and families can compare and purchase ACA-compliant health insurance plans. Plans are organized into metal tiers (Bronze, Silver, Gold, Platinum) based on actuarial value. Eligible enrollees may receive Advanced Premium Tax Credits and Cost-Sharing Reductions to lower their costs. The federal marketplace is accessible at HealthCare.gov; some states operate their own exchanges.
The health insurance premium (保険料, hokenryō) is the monthly payment required to maintain health insurance coverage in Japan. For National Health Insurance, premiums are calculated by each municipality based on prior-year income, household size, and fixed per-person charges. For Shakai Hoken, premiums are a percentage of monthly salary split between employer and employee. Persistent non-payment can result in benefit suspension or legal enforcement action.
The heart is a muscular organ that pumps blood throughout the body via the circulatory system. It beats approximately 60–100 times per minute at rest, supplying oxygen and nutrients to tissues and removing carbon dioxide and waste. Heart disease is among the leading causes of hospitalization in Japan.
Heatstroke is a life-threatening condition in which the body's temperature regulation fails, causing core body temperature to rise dangerously. Japan's hot and humid summers make it extremely common. Symptoms include very high body temperature, altered mental state, and absence of sweating. Move the person immediately to shade or air-conditioning, apply ice packs to the neck, armpits, and groin, and call 119. Air-conditioned train stations and convenience stores serve as emergency cooling refuges.
The High-Cost Medical Expense Benefit (高額療養費, kōgaku ryōyōhi) caps the total out-of-pocket medical costs you pay in a single calendar month. Once your copayments exceed a monthly threshold — which varies by income bracket — your insurer reimburses the excess amount. This protects insured patients from catastrophic medical bills during serious illness or prolonged hospitalization, covering both inpatient and outpatient expenses.
HIPAA (Health Insurance Portability and Accountability Act) is a federal law enacted in 1996 that establishes national standards for the protection of health information. The Privacy Rule gives patients rights over their medical records, including the right to access, copy, and request corrections. The Security Rule requires covered entities to safeguard electronic health information. Providers must obtain patient authorization before sharing information with third parties in most circumstances. Violations can result in significant civil and criminal penalties.
An HMO (Health Maintenance Organization) is an insurance plan type that requires members to choose a primary care provider and obtain referrals to see specialists. HMOs typically only cover care from in-network providers except in emergencies. They usually have lower premiums and out-of-pocket costs compared to PPO plans, but less flexibility in provider choice. Members must use HMO-designated facilities for non-emergency care to have costs covered. HMOs emphasize coordinated, preventive care.
Home health care refers to skilled medical services provided in a patient's home by licensed professionals, including nurses, physical therapists, occupational therapists, and speech therapists. These services are distinct from non-medical home care (such as housekeeping or companion services). Medicare Part A or B may cover home health care when a patient is homebound, under a physician's care, and receiving skilled services. Coverage is based on medical necessity and is subject to prior authorization by many private insurers.
Hospice care provides specialized comfort-focused medical care for individuals with a terminal illness and a life expectancy of six months or less, as certified by two physicians. Hospice prioritizes quality of life and symptom management over curative treatment. Medicare Part A fully covers hospice care (including medications related to the terminal diagnosis, nursing, aide services, and bereavement counseling for families) when care is provided by a Medicare-certified hospice program and the patient elects the hospice benefit. Patients can leave hospice and return to curative care at any time.
Hospital discharge is the formal process by which a patient leaves the hospital after an inpatient stay. The discharge process includes a discharge plan developed by the care team, medication reconciliation, follow-up appointment scheduling, and patient education. Under Medicare regulations, hospitals must provide written Discharge Notice documents explaining patient rights, including the right to request a Quality Improvement Organization review if the patient believes discharge is premature. Discharge to a skilled nursing facility, rehabilitation center, or home health service often requires separate insurance authorization.
Hospital financial assistance programs, also called charity care programs, provide free or discounted care to patients who cannot pay their medical bills. Under the ACA, non-profit hospitals must have written financial assistance policies (FAPs), publicize them, make plain-language summaries available, and not charge patients who qualify for assistance more than the amounts generally billed to insured patients. Applications are typically income-based. Hospitals must provide financial assistance applications before sending bills to collections.
A hospitalist is a physician who specializes in the care of patients during a hospital admission. Unlike patients' regular outpatient doctors, hospitalists are based in the hospital and manage the full course of inpatient care — coordinating tests, medications, specialist consultations, and discharge planning. Patients admitted to a hospital are typically cared for by the on-call hospitalist rather than their own primary care provider. Hospitalists are generally in-network for the hospital but patients should confirm this to avoid surprise billing.
The Health Resources and Services Administration (HRSA) is the primary federal agency for improving healthcare access to people who are uninsured, isolated, or medically vulnerable. HRSA funds Federally Qualified Health Centers (FQHCs), operates the National Health Service Corps, oversees organ donation and transplantation, manages the Ryan White HIV/AIDS Program, and administers the Vaccine Injury Compensation Program. HRSA's Find a Health Center tool (findahealthcenter.hrsa.gov) locates sliding-fee community health centers across the US.
A Health Savings Account (HSA) is a tax-advantaged savings account available to individuals enrolled in a qualifying HDHP. Contributions are pre-tax (or tax-deductible), earnings grow tax-free, and withdrawals for qualified medical expenses are also tax-free — a triple tax benefit. HSA funds roll over year to year and can be invested. After age 65, funds can be withdrawn for any purpose (taxed as income, like a traditional IRA). Annual contribution limits are set by the IRS.
An HSA-eligible expense is a medical cost that qualifies for tax-free payment or reimbursement from a Health Savings Account. The list mirrors FSA-eligible expenses but includes some additional items. After age 65, HSA funds can be used for Medicare premiums (Part B, Part D, Medicare Advantage). HSA funds cannot be used for most health insurance premiums (with exceptions for COBRA, long-term care insurance, and certain continuation coverage). IRS Publication 502 provides the authoritative list. Using HSA funds for non-qualified expenses results in income taxes plus a 20% penalty if under age 65.
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An in-network provider is a doctor, hospital, pharmacy, or other healthcare provider that has a contract with your insurance plan to provide services at negotiated rates. Using in-network providers results in lower cost-sharing — lower copays, coinsurance, and deductibles — compared to out-of-network care. Network directories are available through insurer websites, but should be verified by calling the provider directly, as directories are not always current.
Informed consent is the process by which a healthcare provider explains a proposed treatment, procedure, or research participation to a patient, including its purpose, risks, benefits, and alternatives, so the patient can make a voluntary and educated decision. Patients must have decision-making capacity and the opportunity to ask questions. Consent must be obtained without coercion. For research participation, informed consent is required by federal regulations and overseen by an Institutional Review Board (IRB). Patients can withdraw consent at any time.
A device that delivers medication directly into the lungs through inhalation, used primarily for asthma and chronic obstructive pulmonary disease (COPD). Types include metered-dose inhalers (MDIs), dry powder inhalers (DPIs), and nebulizers. In Japan, inhaled corticosteroids (ICS) and bronchodilators like salbutamol (Ventolin) are the mainstay of asthma management. All inhalers require a prescription and should be used exactly as directed.
Inpatient care means being formally admitted to a hospital and staying overnight or for multiple days to receive medical treatment. This includes surgery, post-operative recovery, intensive monitoring, and management of serious conditions. During a hospital stay in Japan you may be placed in a shared ward or a private room; private rooms carry an additional daily fee not covered by health insurance.
Inpatient care refers to treatment requiring a formal hospital admission, where the patient stays overnight or for multiple days. Inpatient admissions are covered under Medicare Part A and by most private insurance plans, subject to deductibles and coinsurance. The decision to admit a patient as inpatient (versus 'observation status') significantly affects coverage and cost — observation status is classified as outpatient care and may result in higher patient costs, particularly for subsequent skilled nursing facility care under Medicare.
Insomnia is difficulty falling asleep, staying asleep, or waking too early and being unable to return to sleep, resulting in daytime impairment. It is very common in Japan's high-pressure work culture. Causes include stress, anxiety, depression, caffeine, irregular schedules, and medical conditions. Cognitive behavioral therapy and sleep hygiene counseling are first-line treatments before medication.
A formal request submitted to an insurance provider for reimbursement or direct payment of covered medical expenses. In Japan, public health insurance claims are processed automatically between the clinic and the insurer; however, patients must file separately for high-cost medical expense rebates, overseas treatment reimbursement, or benefits from supplemental private policies. Claims typically require receipts, itemized bills, and a physician's certificate.
An insurance claim is a formal request submitted to an insurer for payment of a covered health service. For in-network care, the provider typically submits the claim directly on behalf of the patient. For out-of-network care, the patient may need to submit the claim themselves with supporting documentation. Claims are reviewed for eligibility, coverage, and medical necessity. If a claim is denied, patients have the right to appeal — first through the insurer's internal process, then through external review by an independent organization.
Internal medicine (内科, naika) is the broadest medical specialty, dealing with the diagnosis and non-surgical treatment of diseases affecting internal organs in adults. It covers cardiovascular, respiratory, gastrointestinal, endocrine, kidney, and infectious diseases. In Japan, 内科 is typically the first department to visit for common illnesses such as fever, cough, fatigue, or diabetes management.
The intestines consist of the small intestine, which absorbs most nutrients, and the large intestine (colon), which absorbs water and forms stool. Together they complete digestion. The appendix is a small pouch attached to the large intestine. Bowel complaints including diarrhea and constipation are very common reasons for clinic visits in Japan.
An intramuscular injection delivers medication directly into a muscle, typically the upper arm, thigh, or buttock. The drug is absorbed from the muscle tissue into the bloodstream more slowly than an intravenous injection but more quickly and completely than an oral tablet. Common uses include vaccines, certain antibiotics, anti-inflammatory drugs, and hormonal treatments that require controlled absorption over several hours.
An intravenous injection delivers medication or fluids directly into a vein as a single, rapid bolus dose rather than a slow continuous drip. The drug enters the bloodstream immediately, making it the fastest route of administration. It is used when a rapid effect is needed, such as for emergency pain relief, anti-nausea drugs, contrast agents for imaging, or certain diagnostic substances requiring immediate bioavailability.
An Institutional Review Board (IRB) is an independent committee that reviews and approves research involving human subjects to ensure participant rights, safety, and welfare are protected. IRBs evaluate study protocols, informed consent documents, and ongoing studies. Federal regulations require IRB oversight for research conducted or funded by federal agencies and for studies supporting FDA submissions. IRBs have the authority to approve, modify, or reject research proposals. Members typically include scientists, non-scientists, and community representatives.
A detailed breakdown of all medical services, procedures, medications, and fees charged during a hospital visit, separate from the standard receipt. Since 2010, Japanese hospitals have been legally required to provide an itemized bill upon request at no charge. This document is valuable for verifying billing accuracy, understanding what was treated, and supporting private insurance reimbursement claims.
An itemized medical bill lists every charge for a healthcare encounter individually — each procedure, medication, supply, and service with its corresponding billing code (CPT or HCPCS code) and charge amount. Patients have the right to request an itemized bill from any provider. Reviewing itemized bills is important for identifying billing errors, duplicate charges, or services never received. Common billing errors include upcoding (billing for more complex services than provided) and unbundling (billing procedure components separately instead of as a package).
An intravenous drip (点滴, tenteki) delivers fluids, medications, or nutrients slowly through a needle inserted into a vein, usually in the arm or hand. The drip runs continuously over 30 minutes to several hours at a controlled rate. It is used for dehydration, antibiotic or vitamin delivery, nutritional support, and post-surgical recovery, allowing steady and controlled medication absorption directly into the bloodstream.
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Jaundice is yellowing of the skin and whites of the eyes caused by a buildup of bilirubin in the blood. It indicates a problem with the liver, gallbladder, or bile ducts, or excessive breakdown of red blood cells. Common causes include viral hepatitis, gallstones, alcoholic liver disease, and hemolytic anemia. Jaundice always warrants prompt medical evaluation.
Joint pain (arthralgia) is discomfort, soreness, or aching in one or more joints where two bones meet. Common causes include osteoarthritis, rheumatoid arthritis, gout, and sports injuries. In Japan's aging population, knee osteoarthritis (変形性膝関節症, henkeisei hiza kansetsu-shō) is extremely common. Gout, influenced by diet, is also prevalent, particularly among middle-aged men.
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The kidneys are a pair of bean-shaped organs located in the lower back that filter blood, remove waste and excess fluid as urine, regulate blood pressure, and maintain electrolyte balance. Kidney disease often progresses silently; Japan's annual checkups include urinalysis to detect early signs of kidney dysfunction.
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A medication used to relieve constipation by stimulating bowel movements or softening stool. Types available in Japan include bulk-forming agents (psyllium), stool softeners, osmotic laxatives (magnesium oxide, lactulose), and stimulant laxatives (senna, bisacodyl). Magnesium oxide is the most commonly prescribed laxative in Japan. Many mild formulations are available without a prescription at pharmacies.
The liver is the largest internal organ, located in the upper right abdomen. It performs over 500 functions including metabolizing nutrients, detoxifying chemicals, producing bile for digestion, and synthesizing proteins. Liver function is routinely assessed in Japan's annual health checkups through blood tests measuring enzymes such as ALT and AST.
Long-Term Care Insurance (介護保険, kaigo hoken) is a mandatory social insurance system that funds professional care services for elderly and disabled people. Premium contributions begin at age 40. From age 65, certified individuals can access funded services including home-visit care, adult day care, and nursing home placement. Foreign residents aged 40 and over enrolled in health insurance also pay into and may access this system.
Loss of appetite (anorexia) is a decreased desire to eat, which may lead to unintentional weight loss if prolonged. It can be caused by infections, medications, digestive disorders, depression, cancer, or thyroid problems. Persistent loss of appetite lasting more than a week or accompanied by weight loss should be evaluated to identify the underlying cause.
The lungs are a pair of spongy organs in the chest responsible for gas exchange — bringing oxygen into the bloodstream and expelling carbon dioxide. They are protected by the ribcage and lined by the pleura. Lung health is particularly relevant in Japan due to tuberculosis screening requirements for long-term residents.
Lymph nodes are small, bean-shaped structures distributed throughout the body that filter lymph fluid and house immune cells to fight infection. Swollen lymph nodes (lymphadenopathy) often indicate infection or, less commonly, lymphoma or other cancers. Persistent unexplained swelling should be evaluated by a physician in Japan's internal medicine or oncology departments.
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The Maternal and Child Health Handbook (boshi kenkō techō) is an official booklet issued by municipal offices when a pregnancy is registered. It records all prenatal checkups, labor and delivery details, and the child's growth, vaccinations, and health milestones from birth through school age. Many municipal offices can provide a version in the mother's language. The handbook also contains vouchers for subsidized prenatal checkups and must be carried to every medical appointment.
A cash allowance paid to employed women enrolled in employee health insurance who take approved maternity leave. It covers roughly 67% of the standard daily wage for up to 98 days around childbirth (42 days before, 56 days after). Self-employed or nationally insured individuals receive a separate lump-sum birth allowance instead. Eligibility requires active enrollment at the time of leave.
Medicaid is a joint federal-state health insurance program that provides coverage to low-income individuals and families, including children, pregnant women, elderly adults, and people with disabilities. Eligibility and benefits vary by state. The ACA expanded Medicaid eligibility in participating states to cover adults up to 138% of the federal poverty level. Medicaid is generally free or very low-cost for enrollees. It is administered by state agencies and may go by different names in different states.
Medicaid spend-down is a pathway to Medicaid eligibility for individuals whose income exceeds normal limits but who have high medical expenses. By 'spending down' their income on medical bills to below the Medicaid income threshold, they become eligible for coverage. This is similar to a deductible — once the spend-down amount is met, Medicaid covers the remainder. Spend-down programs are available in some but not all states and primarily serve elderly and disabled individuals with high medical costs.
A medical certificate (診断書, shindansho) is an official document written by a doctor confirming a diagnosis, the nature of an illness or injury, and any recommended rest period or treatment plan. It may be required by employers for sick leave, by schools for absences, for insurance claims, or for immigration and visa-related purposes. A separate document fee of typically 3,000 to 5,000 yen or more is charged for its preparation.
Medical debt is unpaid healthcare bills that a patient owes to a hospital, clinic, or provider. It is the leading cause of personal bankruptcy in the US. Key patient rights regarding medical debt include: the right to an itemized bill, the right to apply for financial assistance before any debt goes to collections, and federal protections limiting how medical debt affects credit scores (credit bureaus began removing medical debt under $500 from reports in 2023). Negotiating with billing departments directly often results in reduced balances.
Medical interpreter services provide qualified language interpretation for patients with limited English proficiency during healthcare encounters. Under Section 1557 of the ACA, covered healthcare entities must provide free interpreter services — either in-person, by phone, or via video remote interpreting. Professional medical interpreters are trained in clinical terminology and ethics, unlike ad hoc interpreters such as family members or bilingual staff. Major language lines include Language Line Solutions and other telephonic interpretation services available at most hospitals.
An official document issued by a hospital or clinic confirming the amount paid by the patient after insurance coverage has been applied. Japanese medical receipts typically show the total billed amount, the insurance-covered portion, and the patient's copayment. These receipts are essential for filing medical expense deductions on annual tax returns (iryōhi kōjo) and for reimbursement claims with private supplemental insurers.
Medicare Part A is hospital insurance provided under the federal Medicare program. It covers inpatient hospital stays, skilled nursing facility care, hospice care, and some home health services. Most people qualify for premium-free Part A at age 65 if they or their spouse worked and paid Medicare taxes for at least 10 years. Part A has deductibles and benefit periods rather than out-of-pocket maximums. Coinsurance applies after extended inpatient stays.
Medicare Part B covers outpatient medical services including doctor visits, preventive care, outpatient surgery, durable medical equipment, and certain laboratory tests. Part B requires a monthly premium (income-adjusted) and has an annual deductible, after which Medicare pays 80% of approved costs and the enrollee pays 20% (with no out-of-pocket cap unless supplemented by Medigap). Late enrollment penalties apply if Part B is not enrolled in promptly when first eligible.
Medicare Part C, or Medicare Advantage, is an alternative to Original Medicare offered by private insurers approved by Medicare. Plans must cover all Part A and B services and often include Part D prescription drug coverage, dental, vision, and hearing benefits. Medicare Advantage plans typically operate as HMOs or PPOs with network restrictions. Monthly premiums may be low or zero, but out-of-pocket costs vary by plan. Enrollment requires simultaneous Part A and B.
Medicare Part D provides prescription drug coverage available as a standalone plan to complement Original Medicare or included in Medicare Advantage plans. Part D plans have their own monthly premiums, deductibles, and formularies. Coverage tiers affect cost: generic drugs in lower tiers are cheapest, while specialty drugs in higher tiers carry higher cost-sharing. A late enrollment penalty applies for those who delay Part D enrollment without other creditable drug coverage.
Medigap (Medicare Supplement Insurance) is private health insurance that helps pay costs not covered by Original Medicare (Parts A and B), such as deductibles, coinsurance, and copays. There are standardized Medigap plan types (labeled A through N) sold by private insurers, with the same basic benefits regardless of insurer. Medigap plans do not cover prescription drugs; Medicare Part D is needed for that. Medigap cannot be used with Medicare Advantage. Enrollment is easiest within 6 months of turning 65 and enrolling in Part B.
A miscarriage is the spontaneous loss of a pregnancy before 20 weeks of gestation, most commonly occurring in the first trimester. In Japan, miscarriage is managed medically in gynecology departments using medication or a curettage procedure. Grief counseling specifically for pregnancy loss is limited but increasingly available through select hospitals and nonprofit organizations. Foreign residents should confirm in advance whether their health insurance covers miscarriage-related medical procedures and any follow-up appointments.
MRI (magnetic resonance imaging) uses strong magnetic fields and radio waves to produce detailed images of soft tissues, organs, and the nervous system without radiation. It excels at imaging the brain, spinal cord, joints, and internal organs. MRI is the preferred modality for diagnosing brain tumors, stroke, herniated discs, ligament injuries, and multiple sclerosis.
The municipal office (市区町村役場, shiku chōson yakuba) is the local government office where residents handle administrative matters including address registration, National Health Insurance enrollment, long-term care insurance, My Number card applications, and family register procedures. For foreign residents, it is the primary administrative entry point in Japan and the required first stop upon arrival for healthcare access.
Muscles are soft tissues composed of fibers capable of contracting to produce movement. There are three types: skeletal (voluntary movement), cardiac (heart), and smooth (involuntary organs). Muscle strains, cramps, and myalgia are common complaints. In Japan, sports injuries and occupational muscle strain are frequent reasons to visit orthopedic or rehabilitation clinics.
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National Health Insurance (国民健康保険, Kokumin Kenkō Hoken) is Japan's public health insurance plan for people not covered by employer-based insurance, including the self-employed, unemployed, students, and retirees. Enrollment is mandatory for all residents registered in Japan, including foreign nationals staying more than three months. Monthly premiums are set by each municipality based on prior-year income and household size.
Natural birth, also called vaginal delivery, refers to giving birth through the birth canal without major surgical intervention. Japan widely encourages natural birth, and many hospitals promote physiological approaches with minimal medical intervention when safe. Pain management options vary by facility, as epidural analgesia is not universally available. Hospital stays after a vaginal birth in Japan are typically four to five days, which is longer than in many Western countries but allows thorough postnatal support.
Nausea is an unpleasant sensation of the urge to vomit. It can be caused by infections (gastroenteritis), motion sickness, pregnancy, medications, food poisoning, or serious conditions such as pancreatitis or appendicitis. In Japan, nausea (吐き気, hakike) is a very common chief complaint and can usually be evaluated at an internal medicine or gastroenterology clinic.
The neonatal intensive care unit (NICU) provides specialized medical care for premature or seriously ill newborns. Japan's NICUs are well-equipped and nationally standardized, accepting preterm infants from as early as 22 weeks gestational age. When a baby is admitted to the NICU, the baby remains in hospital while the mother may be discharged separately. National health insurance covers NICU care, and additional financial support programs exist for families of very-low-birthweight infants.
Nephrology (腎臓内科, jinzō naika) specializes in kidney diseases including chronic kidney disease (CKD), acute kidney injury, glomerulonephritis, and kidney failure requiring dialysis. Japan has one of the world's highest rates of dialysis patients per capita, reflecting the high prevalence of diabetic nephropathy and aging-related kidney decline.
Nerves are bundles of fibers that transmit electrical signals between the brain, spinal cord, and the rest of the body, enabling sensation, movement, and automatic bodily functions. Nerve damage (neuropathy) can cause numbness, tingling, or weakness. Sciatica — compression of the sciatic nerve — is one of the most common nerve complaints seen in Japan.
Neurology (神経内科, shinkei naika) is the specialty dealing with disorders of the nervous system — brain, spinal cord, and peripheral nerves. It treats conditions including stroke, epilepsy, multiple sclerosis, Parkinson's disease, headache disorders, and dementia. Japan's aging population has a high prevalence of stroke and dementia, and neurological services are well developed.
Newborn screening is a public health program that tests infants shortly after birth for rare but treatable metabolic, hormonal, and genetic conditions. In Japan, the program screens for approximately 20 conditions including phenylketonuria and congenital hypothyroidism. The test is performed via a heel-prick blood sample taken three to five days after birth, before hospital discharge. Costs are partially subsidized by local governments, and results are recorded in the Maternal and Child Health Handbook.
The nose is the primary airway for breathing, filtering and warming inhaled air, and housing olfactory receptors for smell. Common nasal conditions include allergic rhinitis (hay fever, 花粉症, kafunshō), sinusitis, and nasal polyps. Japan experiences intense pollen seasons from cedar and cypress trees in spring, making allergic rhinitis very prevalent among residents.
Numbness is a reduced or absent sensation in part of the body, often accompanied by tingling or 'pins and needles.' It can result from pressure on a nerve, poor circulation, diabetes (diabetic neuropathy), multiple sclerosis, or stroke. Sudden numbness or weakness on one side of the face, arm, or leg is a warning sign of stroke and requires emergency evaluation immediately.
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Obstetric ultrasound uses high-frequency sound waves to create images of the fetus, placenta, and uterus during pregnancy. In Japan, ultrasound is routinely performed at nearly every prenatal checkup, making it one of the highest-frequency uses of pregnancy ultrasound worldwide. Images are typically printed and given to parents as keepsakes. Ultrasound monitors fetal growth, position, heartbeat, and amniotic fluid levels, and costs are covered under the prenatal checkup voucher program.
Obstetrics and gynecology (産婦人科, sanfujin-ka) covers pregnancy care, childbirth, and disorders of the female reproductive system including uterus, ovaries, and cervix. In Japan, prenatal care is highly structured with a maternal and child health handbook (母子手帳, boshi techō) issued by the local government to track pregnancy progress.
Off-label drug use refers to prescribing an FDA-approved medication for a purpose, patient population, dosage, or route of administration not included in the FDA-approved labeling. This is legal and common in medical practice — estimates suggest 20–60% of prescriptions in certain specialties are off-label. Physicians may prescribe off-label based on clinical evidence, published studies, or expert consensus. However, insurers may deny coverage for off-label uses unless prior authorization is obtained with supporting clinical justification.
Oncology (腫瘍科, shuyō-ka) is the branch of medicine specializing in the diagnosis and treatment of cancer. Cancer treatments include surgery, chemotherapy, radiation therapy, immunotherapy, and hormone therapy. Japan has some of the world's highest cancer survival rates due to early detection programs for stomach, colon, breast, and cervical cancers.
Open Enrollment is the annual period when individuals can enroll in, change, or drop health insurance coverage without a qualifying life event. For Marketplace plans, federal open enrollment typically runs from November 1 to January 15. Employer-sponsored plans have their own open enrollment windows, usually in the fall. Outside of open enrollment, changes are only allowed during Special Enrollment Periods triggered by qualifying events such as job loss, marriage, or the birth of a child.
Ophthalmology (眼科, ganka) is the specialty dedicated to the medical and surgical care of the eyes. It covers prescription of eyeglasses, contact lens fitting, and treatment of glaucoma, cataracts, diabetic retinopathy, and eye infections. Japan has an extremely high prevalence of myopia, and optometry services integrated with ophthalmology are widely available.
Orthopedics (整形外科, seikei geka) is the specialty concerned with bones, joints, muscles, ligaments, tendons, and nerves of the musculoskeletal system. It treats fractures, sprains, arthritis, herniated discs, and sports injuries. In Japan, orthopedic clinics are among the most commonly visited specialty clinics, particularly for lower back pain (腰痛, yōtsū) and knee osteoarthritis.
Otolaryngology, commonly called ENT (Ear, Nose, and Throat), covers disorders of the ear, nose, throat, sinuses, and upper airways. In Japan, ENT clinics (耳鼻咽喉科, jibi-inkōka) are frequently visited for allergic rhinitis (hay fever), sinusitis, otitis media, vertigo, and tonsillitis. ENT clinics are abundant and typically accessible without referral.
An out-of-network provider does not have a contract with your insurance plan. Using one typically results in higher costs: higher deductibles, higher coinsurance, and sometimes full billing at list prices. Some plan types (HMO, EPO) do not cover out-of-network care at all except in emergencies. Balance billing — being billed the difference between the provider's charge and the insurer's payment — is a risk when going out of network, though the No Surprises Act restricts this in emergency settings.
The out-of-pocket maximum is the most you will have to pay for covered in-network services in a plan year. Once you reach this limit — through deductibles, copays, and coinsurance combined — your insurance covers 100% of covered services for the rest of the year. ACA-compliant plans set federal limits on out-of-pocket maximums annually. Premiums, out-of-network costs, and services not covered by the plan do not count toward this limit.
Outpatient care refers to medical services received without being admitted to a hospital overnight. It includes doctor consultations, diagnostic tests, minor procedures, injections, and follow-up visits. The patient arrives, receives care, and returns home the same day. Most routine medical care in Japan, including specialist visits and scheduled examinations, is provided through outpatient departments or standalone clinics.
Outpatient care includes any medical treatment, procedure, or visit where the patient does not require an overnight hospital stay. This includes doctor office visits, same-day surgery, emergency room visits, urgent care, imaging, and laboratory tests. Outpatient care is generally subject to different cost-sharing than inpatient: under Medicare, outpatient services fall under Part B rather than Part A, which has different deductibles and coinsurance. Many procedures that previously required hospitalization are now done on an outpatient basis.
The ovaries are a pair of small glands in the female pelvis that produce eggs (ova) and the hormones estrogen and progesterone. Conditions include ovarian cysts, polycystic ovary syndrome (PCOS), and ovarian cancer. Ovarian cysts are commonly detected during routine ultrasound examinations performed in Japan's annual health checkups or gynecological consultations.
Medication that can be purchased at a pharmacy or drugstore without a physician's prescription. Japan classifies OTC drugs into three categories based on risk: Class 1 (pharmacist consultation required), Class 2 (pharmacist available), and Class 3 (lower risk, self-selection allowed). Common OTC products include cold remedies, antihistamines, pain relievers, and digestive aids. Some OTC drugs in Japan differ in formulation or dose from equivalent products abroad.
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A medication that reduces pain perception. Common OTC painkillers in Japan include acetaminophen (Calonal, Tylenol) and ibuprofen (Bufferin EX, Ibuprofen A). Stronger opioid-based painkillers are tightly controlled and only dispensed in hospitals under strict prescription. NSAIDs are widely used for headaches, menstrual pain, dental pain, and musculoskeletal discomfort. Always check labeling for maximum daily dose.
Palpitations are sensations of the heartbeat being rapid, fluttering, pounding, or irregular. They are often harmless and triggered by caffeine, stress, or exercise, but can indicate cardiac arrhythmias, thyroid disease, anemia, or anxiety disorders. Palpitations accompanied by chest pain, fainting, or severe shortness of breath require immediate medical evaluation.
The pancreas is an organ located behind the stomach that has both digestive (producing enzymes) and endocrine functions (producing insulin and glucagon to regulate blood sugar). Pancreatitis (inflammation) causes severe abdominal pain, while pancreatic cancer has poor prognosis. Diabetes mellitus, caused by insulin dysfunction, is a major public health concern in Japan.
Pediatrics (小児科, shōnika) is the branch of medicine dealing with the health and medical care of infants, children, and adolescents up to age 15–18. It covers routine checkups, vaccinations, development assessment, and treatment of childhood illnesses. Japan's child health program offers free municipal health checkups at key developmental milestones.
A physical examination is a hands-on assessment by a doctor to evaluate your general health. The doctor checks vital signs such as blood pressure, pulse, and temperature, then examines body systems including the heart, lungs, abdomen, and reflexes using tools such as a stethoscope and reflex hammer. It may be conducted as part of a routine health checkup or performed to investigate specific symptoms a patient is experiencing.
A placebo is an inactive substance, device, or procedure used in clinical trials as a comparison to the experimental treatment. Participants may receive either the real treatment or a placebo without knowing which they received — this is called blinding. The placebo effect refers to real physiological improvements some patients experience even when receiving an inactive treatment, due to expectation and belief. Placebos are critical to rigorous clinical research design. Outside of trials, providing placebos without disclosure to patients raises ethical concerns.
Poisoning occurs when a harmful substance is ingested, inhaled, or absorbed through the skin. Japan's Poison Information Centers (Chūdoku 110) offer 24-hour telephone advice: 072-727-2499 in Osaka and 029-852-9999 in Tsukuba. For life-threatening poisoning, call 119 immediately. Always bring the container or label of any suspected toxic substance to the hospital so that doctors can identify and treat the poison as quickly as possible.
Postnatal care refers to medical and practical support provided to a mother and newborn in the weeks following birth. In Japan, hospital stays after delivery are typically four to six days, during which nurses provide hands-on guidance for newborn care and breastfeeding. After discharge, local health centers (hokenjo) offer free home visits by a public health nurse within the first two weeks. Postnatal care centers (sango care centers) are increasingly available for mothers needing additional rest and support.
Postpartum depression is a mood disorder affecting women after childbirth, characterized by persistent sadness, anxiety, exhaustion, and difficulty bonding with the baby. In Japan, awareness has grown in recent years. Local health centers screen for postpartum depression at one-month and four-month infant checkups using standardized questionnaires. Foreign residents may find culturally appropriate Japanese-language counseling limited; English-speaking mental health professionals in major cities and some international hospitals can provide suitable support.
A PPO (Preferred Provider Organization) is an insurance plan offering more flexibility than an HMO. Members can see any doctor without a referral, including out-of-network providers, though in-network care costs less. PPOs typically have higher premiums than HMOs but allow self-referrals to specialists. Out-of-network coverage usually involves higher deductibles and coinsurance. PPOs suit people who value provider choice, travel frequently, or have complex conditions requiring multiple specialists.
Pregnancy is the period during which a developing fetus grows inside the uterus, typically lasting about 40 weeks from the last menstrual period. In Japan, upon confirming pregnancy with a doctor, register at your local municipal office to receive the Maternal and Child Health Handbook (boshi techo) and prenatal checkup vouchers. Foreign residents enrolled in national health insurance are covered for most obstetric care, including routine prenatal visits and delivery.
A premium is the monthly amount you pay to maintain your health insurance coverage, regardless of whether you use medical services that month. Premiums are paid to the insurance company and do not count toward your deductible or out-of-pocket maximum. Employer-sponsored plans often split premiums between employer and employee. Marketplace plans may qualify for Advanced Premium Tax Credits (APTC) that reduce monthly costs for eligible lower-income enrollees.
Prenatal checkups are regular medical appointments throughout pregnancy to monitor the health of both mother and developing baby. In Japan, local governments provide a booklet of free checkup vouchers (kenshin hyō) when you register your pregnancy. Checkups are typically monthly in the first and second trimesters and more frequent in the third. English-speaking obstetric clinics exist in major cities but may be unavailable in rural areas, so plan ahead.
A prescription (処方箋, shohōsen) is a written or electronic instruction from a licensed doctor authorizing a patient to obtain specific medication from a pharmacy. After a consultation, the doctor issues the prescription and the patient takes it to a dispensing pharmacy (調剤薬局) to receive the medicine. Insurance coverage applies to listed prescription drugs, significantly reducing the patient's out-of-pocket medicine costs.
A medication that legally requires a written order (prescription) from a licensed physician or dentist before it can be dispensed by a pharmacist. In Japan, prescriptions are written on a standardized form and can be taken to any registered dispensing pharmacy (chōzai yakkyoku). Prescriptions are typically valid for four days and cannot be refilled without a new doctor's visit. Insurance coverage applies to covered prescription drugs at the standard copayment rate.
Preventive care refers to services designed to prevent illness or detect health conditions early before symptoms develop. Under the ACA, most insurance plans must cover a set of preventive services at no cost to the patient — with no deductible, copay, or coinsurance — when provided by an in-network provider. These services include annual wellness visits, vaccinations, cancer screenings (mammograms, colonoscopies), blood pressure and cholesterol checks, and certain medications for high-risk patients. The required services are based on recommendations from USPSTF, ACIP, and HRSA.
A Primary Care Provider (PCP) is a physician, nurse practitioner, or physician assistant who serves as a patient's main healthcare contact for routine and preventive care. PCPs handle annual wellness visits, manage chronic conditions, prescribe medications, and coordinate referrals to specialists. Under HMO plans, designating a PCP is required and the PCP serves as the gatekeeper to specialized care. PCPs may be family medicine doctors, general internists, or pediatricians.
Prior auth is the shortened term for prior authorization, the insurer approval required before receiving certain medical services or medications. The terms are interchangeable. Without prior auth, the insurer may deny the claim or require the patient to pay full cost. Obtaining prior auth is the provider's responsibility in most cases, though patients can check with their insurer to confirm it has been obtained before a scheduled procedure. Prior auth decisions must meet federally mandated timeframes.
Prior authorization (PA) is approval from your insurance company required before you receive certain medical services, medications, or procedures. Without it, the insurer may deny the claim or pay a reduced amount. Common services requiring PA include surgery, MRI/CT scans, brand-name drugs, specialist visits under some plans, and durable medical equipment. The requesting provider submits clinical justification; approval decisions are typically required within set timeframes under state law.
A provider network is the set of doctors, hospitals, pharmacies, and other healthcare facilities that have contracted with an insurance plan to provide services at negotiated rates. Using in-network providers results in lower cost-sharing for the patient. Networks vary in size and geography — some plans have broad national networks while others, particularly HMO and EPO plans, have narrower local networks. Patients should verify network status directly with both the insurer and the provider, as directories can be outdated.
Psychiatry (精神科, seishin-ka) is the specialty focused on diagnosing and treating mental, behavioral, and emotional disorders including depression, anxiety, schizophrenia, and bipolar disorder. In Japan, 心療内科 (shinryō naika, psychosomatic medicine) is also commonly visited for stress-related conditions and may feel more accessible to some patients.
A public health center (保健所, hokenjo) is a government-run facility providing community health services including infectious disease control, tuberculosis screening, mental health consultations, maternal and child health programs, and food sanitation oversight. They issue health-related certificates, manage vaccination programs, and coordinate disease surveillance. Some centers offer multilingual consultations or referrals to interpretation services for foreign residents.
Pulmonology (呼吸器科, kokyūki-ka) is the specialty dealing with diseases of the lungs and respiratory tract, including asthma, COPD, pneumonia, lung cancer, and tuberculosis. Pulmonologists use spirometry (breathing tests), chest imaging, and bronchoscopy for diagnosis. Japan mandates tuberculosis screening for certain foreign residents and long-term visa applicants.
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A qualifying life event is a change in circumstances that makes a person eligible for a Special Enrollment Period outside of open enrollment. Qualifying events include loss of health coverage (job loss, aging off a parent's plan at 26, loss of Medicaid eligibility), change in household (marriage, divorce, birth, adoption, death), change in residence to a new plan area, and certain other situations such as gaining citizenship or leaving incarceration. Each qualifying event has a specific enrollment window, typically 60 days.
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Radiology (放射線科, hōshasen-ka) uses imaging technologies — X-ray, CT scan, MRI, ultrasound, and nuclear medicine — to diagnose and guide treatment of diseases. Radiologists interpret imaging studies ordered by other departments. In Japan, imaging technology is highly advanced; CT and MRI machines are numerous and wait times for non-emergency scans are relatively short.
A rash is a change in the skin's appearance — including redness, blistering, swelling, or texture changes — often covering multiple areas. Causes include allergic reactions, eczema, contact dermatitis, viral infections (chicken pox, measles), and autoimmune diseases. A widespread rash with fever and difficulty breathing may indicate a severe allergic reaction (anaphylaxis) requiring emergency care.
A referral is a formal recommendation or authorization from your primary care provider (PCP) to see a specialist or receive a specific service. HMO plans generally require a referral for specialist visits to be covered; PPO plans often do not. A referral typically contains patient information, the reason for the visit, and relevant clinical history. Without a required referral, the specialist visit may not be covered by insurance, leaving the patient responsible for the full cost.
A referral letter (紹介状, shōkaijō) is a formal document issued by your primary care doctor or local clinic introducing you to a specialist or larger hospital. It contains your medical history, current diagnosis, test results, and the reason for the referral. Presenting a referral letter at a large hospital waives the selected hospital fee and allows smooth information transfer between your doctors.
The Residence Card (在留カード, zairyū kādo) is an official ID card issued by Japan's Immigration Services Agency to foreign nationals holding medium- to long-term residence status. It displays the holder's name, nationality, date of birth, address, residence status, and period of stay. The card is required when enrolling in health insurance, opening a bank account, signing a lease, and many other administrative procedures.
A pension payment provided to insured individuals who have reached retirement age and met the required contribution period. In Japan, this typically begins at age 65 under the national pension system. Foreign residents who have paid into the system for at least ten years may be eligible, and lump-sum withdrawal is available to those leaving Japan who do not meet the minimum period.
A runny nose (rhinorrhea) is excessive discharge of mucus from the nose. It is most commonly caused by the common cold, allergic rhinitis (hay fever), or sinusitis. In Japan, spring cedar pollen season (February to April) triggers widespread allergic rhinitis, making runny nose one of the most common seasonal complaints. Over-the-counter antihistamines are widely available at pharmacies.
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Section 1557 of the Affordable Care Act prohibits discrimination in healthcare on the basis of race, color, national origin, sex, age, or disability in programs receiving federal funding. It requires covered healthcare entities to provide meaningful access for people with limited English proficiency, including free qualified interpreter services and translated written materials. Patients have the right to a competent medical interpreter at no cost; using family members as interpreters is discouraged for clinical encounters. Complaints can be filed with HHS Office for Civil Rights.
A seizure is a sudden, uncontrolled burst of electrical activity in the brain that can cause changes in behavior, movements, feelings, and levels of consciousness. Seizures can be convulsive (with shaking) or non-convulsive. Epilepsy is a chronic condition involving recurrent seizures. A first seizure or prolonged seizure lasting more than 5 minutes is a medical emergency.
The selected hospital fee (選定療養費, sentei ryōyōhi) is an extra charge levied by large Japanese hospitals when a patient visits without a referral letter from a smaller clinic. Since 2016, hospitals with 200 or more beds must collect this fee, typically ranging from 5,000 to 10,000 yen or more, to discourage patients from bypassing neighborhood clinics and going directly to large hospitals for routine care.
Shortness of breath (dyspnea) is the sensation of not being able to breathe easily or getting enough air. It can result from lung conditions (asthma, pneumonia, COPD), heart problems, anemia, or anxiety. Sudden severe shortness of breath accompanied by chest pain or bluish lips is a medical emergency and warrants calling 119 in Japan.
The skin is the body's largest organ, forming a protective barrier against pathogens, regulating temperature, and providing sensory information. Common skin conditions in Japan include atopic dermatitis, contact dermatitis, and tinea (fungal infection). Japan's humid summers increase the incidence of heat rash and fungal skin complaints.
A skin test involves applying a small amount of a suspected allergen or substance to the skin by pricking, scratching, or injecting it just beneath the surface. After 15 to 20 minutes for prick tests or 48 to 72 hours for patch tests, the site is examined for redness, swelling, or a raised wheal indicating a reaction. Skin tests identify specific allergies and are also used to detect past tuberculosis exposure.
A sliding fee scale is a payment structure that adjusts the cost of healthcare services based on the patient's income and family size. Federally Qualified Health Centers (FQHCs) are required by law to offer sliding fee discounts to all patients regardless of insurance status. Fees are calculated as a percentage of the federal poverty level: patients at or below 100% FPL pay minimal or no fees, while those with higher incomes pay on a graduated scale up to the full charge. Documentation of income is required.
A sore throat is pain, scratchiness, or irritation of the throat, often worsened by swallowing. Most sore throats are caused by viral infections such as the common cold or influenza. Bacterial causes, particularly Group A Streptococcus (strep throat), require antibiotic treatment. Rapid strep tests are available at many clinics in Japan for quick diagnosis.
A Special Enrollment Period (SEP) is a window outside of the annual open enrollment period during which individuals can enroll in or change health insurance due to a qualifying life event. Qualifying events include losing other coverage (job loss, end of COBRA), getting married or divorced, having a baby or adopting a child, moving to a new coverage area, or gaining citizenship. SEPs typically last 60 days from the qualifying event. Marketplace SEPs require documentation of the qualifying event.
A specialist is a physician with advanced training and board certification in a specific area of medicine, such as cardiology, oncology, orthopedics, or dermatology. Specialists focus on diagnosing and treating conditions within their area of expertise, often after referral from a primary care provider. Specialist visits typically carry higher copays than PCP visits. HMO plans usually require a referral; PPO plans typically allow direct access. Seeing an in-network specialist is critical for cost control.
The spine, or vertebral column, is a series of 33 vertebrae stacked vertically that encase and protect the spinal cord. It provides structural support for the body and enables movement. Back pain related to the spine is extremely common in Japan, and orthopedic clinics (整形外科, seikei geka) are frequently visited for this complaint.
A sputum test analyzes mucus coughed up from the lungs and airways. The patient is asked to cough deeply to produce a sample from the lower respiratory tract, which is then examined under a microscope and cultured to identify bacteria, fungi, or viruses. It is used to diagnose pneumonia, tuberculosis, and chronic respiratory conditions, and to determine which antibiotic or antifungal treatment will be most effective.
Step therapy, sometimes called 'fail first,' is a cost-control practice by insurers that requires patients to try and fail on lower-cost medications before the insurer will cover a more expensive drug. For example, a plan may require a patient to try a generic drug first; if it is ineffective or causes adverse effects, the insurer then authorizes the brand-name or specialty drug. Many states have enacted step therapy exception laws requiring insurers to provide override processes when step therapy is clinically inappropriate.
A class of anti-inflammatory drugs derived from or mimicking cortisol, used to reduce swelling, suppress immune responses, and treat conditions like asthma, eczema, allergic reactions, and autoimmune diseases. In Japan, topical steroid creams are commonly prescribed for skin conditions like atopic dermatitis. Oral and injectable steroids require a prescription and careful monitoring due to side effects with long-term use.
The stomach is a muscular sac in the upper abdomen that receives food from the esophagus, mixes it with gastric acid and enzymes, and begins digestion before passing contents to the small intestine. Japan has a high incidence of stomach cancer, and endoscopy (胃カメラ, i-kamera) is commonly recommended for screening, especially after age 40.
A stroke happens when blood supply to part of the brain is blocked or a blood vessel ruptures, causing brain damage. Use the FAST acronym: Face drooping, Arm weakness, Speech difficulty, Time to call 119. Japan has a high stroke rate and many hospitals are designated stroke care centers with specialized rapid-treatment protocols. Every minute without treatment increases permanent disability risk, so calling 119 without delay is essential.
A tablet placed under the tongue where it dissolves and is absorbed rapidly into the bloodstream through the sublingual mucosa. This route avoids first-pass metabolism in the liver, allowing faster and more complete absorption than swallowed tablets. In Japan, sublingual tablets are used for nitroglycerine (chest pain emergency), allergy immunotherapy (house dust mite and cedar pollen), and some hormonal therapies. Do not swallow or chew sublingual tablets.
A solid dosage form inserted into the rectum or vagina where it dissolves to release medication. Rectal suppositories are commonly used in Japan for fever reduction in children who cannot swallow tablets, as well as for treating constipation and hemorrhoids. They are absorbed through the rectal mucosa, bypassing the digestive system for faster action. Refrigerate suppositories unless instructed otherwise and insert after softening briefly in the hand.
A medical procedure in which a physician makes incisions into the body to treat injury, disease, or structural abnormality. Surgery in Japan is performed in designated operating theatres at hospitals and is covered by health insurance under the standard copayment structure. Consent forms are required before any surgical procedure and are typically provided in Japanese, though larger hospitals with international patient departments may offer translated versions.
The surgery department (外科, geka) handles conditions requiring operative intervention, including removal of the appendix, gallbladder, tumors, and repair of hernias and trauma injuries. In Japan, surgeries are performed in hospitals rather than clinics. Before elective surgery, patients receive detailed written explanations (インフォームドコンセント, infōmudo konsento — informed consent) in Japanese.
A surprise bill is an unexpected medical charge a patient receives when they receive care from an out-of-network provider without knowing it — for example, when an out-of-network anesthesiologist assists during an in-network surgery, or when a patient is taken to an out-of-network ER during an emergency. The No Surprises Act, effective January 2022, restricts surprise billing in emergency situations and for certain ancillary services, requiring providers to charge only in-network cost-sharing rates and prohibiting balance billing in covered situations.
Swelling (edema) is the accumulation of fluid in body tissues, causing puffiness or enlargement. It commonly affects the legs, ankles, and feet. Causes include heart failure, kidney disease, liver cirrhosis, venous insufficiency, and allergic reactions. Sudden facial or throat swelling after eating or medication is a sign of anaphylaxis and requires immediate emergency treatment.
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Telehealth refers to healthcare services delivered remotely via phone, video, or secure messaging platforms. Services include virtual doctor consultations, mental health therapy, chronic disease management, and prescription refills. Telehealth expanded dramatically during the COVID-19 pandemic. Coverage and cost-sharing vary by plan; many insurers now cover telehealth visits at parity with in-person visits. Telehealth is particularly useful for follow-up appointments, minor conditions, and patients in rural areas or with mobility limitations.
A notification and payment arrangement used when a patient's injury or illness was caused by a third party, such as in a traffic accident. The patient must notify their insurer to allow public health insurance to cover treatment initially, with the insurer later seeking reimbursement from the at-fault party or their liability insurer. Failing to report a third-party cause can complicate or void coverage.
The throat (pharynx and larynx) is the passageway for air and food, and contains the vocal cords. Common conditions include pharyngitis (sore throat), tonsillitis, and laryngitis. Throat complaints are among the most frequent reasons people visit clinics in Japan, particularly during cold and flu season in winter.
The thyroid is a butterfly-shaped gland in the front of the neck that produces hormones regulating metabolism, heart rate, and body temperature. Thyroid disorders including hypothyroidism, hyperthyroidism (Graves' disease), and thyroid nodules are common in Japan, particularly among women. Blood tests for thyroid function are included in many comprehensive health checkups.
A semi-solid medication applied directly to the skin surface to treat local conditions such as eczema, psoriasis, infections, inflammation, or pain. Japanese pharmacies carry a wide range of OTC topical ointments for rashes, wounds, and insect bites. Prescription ointments include corticosteroid creams, tacrolimus for atopic dermatitis, and antibacterial agents. Always apply to clean, dry skin and wash hands after use unless hands are the treatment area.
Triage is the medical process of sorting patients by urgency so that the most critically ill receive care first. In Japanese hospital emergency rooms, a triage nurse assesses each patient at the entrance and assigns a color-coded priority level. Patients with minor complaints may wait several hours while critical cases are treated immediately. Understanding how triage works helps foreign residents set realistic expectations about wait times when using Japan's emergency services.
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Ultrasound imaging uses high-frequency sound waves to produce real-time images of internal organs, blood vessels, and developing fetuses. It is painless, uses no radiation, and is safe in pregnancy. Common uses include assessing abdominal organs (liver, gallbladder, kidneys), thyroid, ovaries, and monitoring fetal development during prenatal checkups.
Unconsciousness means a person is unresponsive and cannot be woken, which may signal cardiac arrest, stroke, severe head injury, or seizure. Call 119 immediately. While waiting for paramedics, check that the airway is clear and monitor breathing; begin CPR if there is no pulse. Never leave an unconscious person alone or give them food or liquid. Prompt bystander action in the first minutes is critical to a positive outcome.
Unexplained weight loss is losing more than 5% of body weight over 6–12 months without intentional dieting or increased exercise. It can signal serious underlying conditions including cancer, diabetes, hyperthyroidism, depression, gastrointestinal disease, or chronic infections such as tuberculosis. Thorough evaluation including blood tests and imaging is warranted.
An urgent care center is a walk-in medical facility for conditions that need prompt attention but are not life-threatening emergencies. Common reasons to visit include minor fractures, sprains, infections, fever, and minor wounds. Urgent care centers are open beyond regular office hours, often evenings and weekends, and typically cost significantly less than emergency rooms. Most accept insurance; copays usually range from $25–$75 in-network. They are not appropriate for chest pain, stroke symptoms, or severe injuries.
Urinalysis is the examination of a urine sample to detect abnormalities including protein, glucose, blood, bacteria, and white cells. It screens for urinary tract infections, kidney disease, diabetes, and certain metabolic conditions. In Japan, urinalysis is a routine component of annual health checkups and is used to detect kidney dysfunction early before symptoms appear.
A urine culture is a laboratory test that detects bacteria or fungi in a urine sample by placing it on a growth medium and incubating it for 24 to 48 hours. If microorganisms grow, the specific type is identified and tested against antibiotics to determine the most effective treatment. It is primarily used to confirm urinary tract infections and to guide antibiotic prescribing decisions accurately.
Urology (泌尿器科, hinyōki-ka) is the specialty that deals with diseases of the urinary tract in both sexes and the male reproductive system. It treats conditions such as urinary tract infections, kidney stones, benign prostatic hyperplasia (BPH), bladder cancer, and erectile dysfunction. Prostate-specific antigen (PSA) testing for prostate cancer screening is available in Japan's annual checkup programs.
The uterus is a hollow, pear-shaped organ in the female pelvis where a fetus develops during pregnancy. Conditions affecting the uterus include fibroids, endometriosis, and uterine cancer. In Japan, cervical cancer screening (子宮頸がん検診, shikyūkei-gan kenshin) is offered free every two years to women aged 20 and over through municipal health programs.
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Vaccination is the administration of a vaccine to stimulate the immune system to produce immunity against a specific pathogen. In Japan, routine vaccinations for children are provided through municipal public health programs, many at no cost. Adults can receive influenza, pneumococcal, hepatitis B, and other vaccines at clinics, sometimes with subsidy for eligible age groups.
Vomiting is the forceful expulsion of stomach contents through the mouth. Common causes include gastroenteritis, food poisoning, excessive alcohol, pregnancy (morning sickness), and chemotherapy. Repeated vomiting causing dehydration, vomiting blood (hematemesis), or vomiting alongside severe headache or abdominal pain requires urgent medical evaluation.
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Workers' Compensation Insurance (労災保険, rōsai hoken) covers injuries, illnesses, and deaths that occur directly as a result of work duties or the commute to and from work. It covers 100% of medical treatment costs with no copayment, as well as lost wages, rehabilitation, and survivor benefits. All Japanese employers are required by law to enroll their workers in this scheme regardless of employment type or nationality.
Last reviewed: September 2026