US Medical Term · tests
Fasting Blood Glucose
Glucosa en ayunas
What it means
A fasting blood glucose test measures your glucose after you fast (not eating or drinking, except for water) for at least 8 hours. Glucose is a type of sugar. MedlinePlus lists fasting plasma glucose (FPG), fasting blood sugar (FBS) and fasting blood glucose (FBG) among the other names for blood glucose tests, and says the fasting test is often used to screen for or monitor prediabetes or diabetes. A health care professional takes a blood sample from a vein in your arm, using a small needle. In the MedlinePlus Medical Encyclopedia, a fasting level of 70 to 99 mg/dL is considered normal, a level of 100 to 125 mg/dL means impaired fasting glucose, a type of prediabetes, and a level of 126 mg/dL or higher usually means diabetes.
Fasting Blood Glucose in Spanish
- Spanish term
- Glucosa en ayunas
- Gender and article
- feminine: la glucosa en ayunas
- Pronunciation
- gloo-KOH-sah ehn ah-YOO-nahs
| Other Spanish terms | Where it is used | Note |
|---|---|---|
| glucemia en ayunas | General | Listed by MedlinePlus en español among the other names of the blood glucose test; its encyclopedia article writes prueba de glucemia en ayunas. |
| glucosa plasmática en ayunas | General | Listed by MedlinePlus en español among the other names of the test, with the abbreviation GPA. |
| glucosa en plasma en ayunas | General | Form used by the NIDDK's Spanish page, which keeps the English abbreviation FPG. |
Glucosa en ayunas appears on MedlinePlus en español inside the name of the test, prueba de glucosa en ayunas, also written prueba de glucosa en sangre en ayunas. Glucosa is feminine: the MedlinePlus en español encyclopedia writes una alteración de la glucosa en ayunas for impaired fasting glucose. That encyclopedia article uses glucemia: the fasting test there is the prueba de glucemia en ayunas. MedlinePlus en español also lists glucosa plasmática en ayunas (GPA) among the other names, and the NIDDK's Spanish page calls the test prueba de glucosa en plasma en ayunas, keeping the English abbreviation FPG.
En ayunas is the phrase for "fasting": the encyclopedia glosses it as not having eaten anything for at least 8 hours. The verb is ayunar, which the NIDDK page explains as not eating or drinking anything except sips of water. The Spanish encyclopedia article prints results with the unit mg/dl, where the English one prints mg/dL. A related word is prediabetes, spelled the same in both languages.
Phrases for an appointment
What a patient or a clinician might say, in English and Spanish:
| Who | English | Spanish |
|---|---|---|
| Clinician | I am going to order a fasting blood glucose test for you. | Le voy a pedir una prueba de glucosa en ayunas. |
| Patient | How many hours do I have to fast before the test? | ¿Cuántas horas tengo que ayunar antes de la prueba? |
| Clinician | You need to fast for at least eight hours before the test. | Necesita ayunar por al menos ocho horas antes de la prueba. |
| Patient | Can I drink water while I am fasting? | ¿Puedo tomar agua mientras estoy en ayunas? |
| Clinician | When was the last time you ate or drank anything other than water? | ¿Cuándo fue la última vez que comió o bebió algo que no fuera agua? |
| Patient | I had breakfast two hours ago. Do we need to change the date of the test? | Desayuné hace dos horas. ¿Tenemos que cambiar la fecha de la prueba? |
| Clinician | We are going to take a blood sample from a vein in your arm. | Le vamos a tomar una muestra de sangre de una vena del brazo. |
| Patient | My fasting glucose came back at 110. What does that number mean? | Mi glucosa en ayunas salió en 110. ¿Qué significa ese número? |
In 9 languages
| Language | Term |
|---|---|
| English | Fasting Blood Glucose |
| Spanish (Español) | Glucosa en ayunas |
| Chinese (中文) | 空腹血糖 |
| Korean (한국어) | 공복혈당 |
| Vietnamese (Tiếng Việt) | Xét nghiệm đường huyết lúc đói |
| Filipino (Tagalog) | Fasting Blood Glucose |
| Portuguese (Português) | Glicemia em jejum |
| Thai (ภาษาไทย) | การตรวจน้ำตาลในเลือดขณะอดอาหาร |
| Japanese (日本語) | 空腹時血糖 |
Where you'll see it
Related terms
Your right to an interpreter in the United States
If English is not your primary language and you have difficulty communicating in English, you may need an interpreter or a translated document when you visit a doctor or dentist, go to the emergency room or pick up a prescription. The U.S. Department of Health and Human Services Office for Civil Rights states that two federal laws, Title VI of the Civil Rights Act of 1964 and Section 1557 of the Affordable Care Act, require programs that receive its funding to provide language access services free of charge.
You can ask when you make the appointment or at the front desk: "I need an interpreter, please." «Necesito un intérprete, por favor.»
More terms: Blood and immune system
All terms in this area: Blood and immune system — Sangre y sistema inmunitario
Sources
- Blood Glucose Test: MedlinePlus Medical Test — MedlinePlus, National Library of Medicine
- Prueba de glucosa en la sangre: Prueba de laboratorio de MedlinePlus — MedlinePlus en español, Biblioteca Nacional de Medicina
- Blood sugar test: MedlinePlus Medical Encyclopedia — MedlinePlus, National Library of Medicine
- Examen de glucemia: MedlinePlus enciclopedia médica — MedlinePlus en español, Biblioteca Nacional de Medicina
- Pruebas y diagnóstico de la diabetes — Instituto Nacional de la Diabetes y las Enfermedades Digestivas y Renales (NIDDK), NIH
- Limited English Proficiency (LEP): Your Right to Language Assistance Services — U.S. Department of Health and Human Services, Office for Civil Rights
This page is a language reference. It is not medical advice.
Last reviewed: October 8, 2026