US Medical Term · symptoms
Lethargy
Letargo
Also: Apatía (regional variant)
In 9 languages
| Language | Term |
|---|---|
| English | Lethargy |
| Spanish (Español) | Letargo |
| Chinese (中文) | 嗜睡 |
| Korean (한국어) | 기면 |
| Vietnamese (Tiếng Việt) | Hôn mê nhẹ |
| Filipino (Tagalog) | Lethargy |
| Portuguese (Português) | Letargia |
| Thai (ภาษาไทย) | ความซึมเซา |
| Japanese (日本語) | 傾眠 |
What it means
Lethargy is a state of extreme tiredness, drowsiness, and reduced alertness that goes beyond normal fatigue. A person who is lethargic may be hard to rouse, respond slowly, and lack the usual energy or interest in surroundings. In infants and young children, lethargy is always a serious warning sign requiring immediate evaluation. In adults, causes include severe infections, head injury, stroke, metabolic disorders, thyroid problems, medication effects, and overdose. Sudden-onset lethargy, especially with fever or confusion, is a medical emergency. Always seek prompt medical attention if someone appears significantly more drowsy or unresponsive than usual.
How to say it
Sentences a patient might use with a doctor, nurse, pharmacist, or insurer:
My child is very hard to wake up and seems unusually drowsy.
Mi hijo es muy difícil de despertar y parece inusualmente somnoliento.
I feel so sluggish and drowsy that I can barely stay awake.
Me siento tan lento y somnoliento que apenas puedo mantenerme despierto.
She has been unresponsive and barely opening her eyes since this morning.
Ha estado sin respuesta y apenas abriendo los ojos desde esta mañana.
Where you'll see it
Related ICD-10-CM category
R53 Malaise and fatigueRelated terms
Sources
Last reviewed: September 2026