Malaise
A general sense of being unwell, without a specific localising symptom.
What it means
Malaise is a diffuse sense of being unwell — a discomfort or unease a person cannot localise or describe precisely. From the French, meaning discomfort.
It is deliberately non-specific, and that is exactly what makes it useful. A patient saying "I just don't feel right" is providing real clinical information, and is often correct.
Malaise accompanies almost any infection, and also appears in anaemia, thyroid disease, kidney disease, depression, cancer and medication side effects.
In practice
Notes commonly record "malaise and lethargy" together as a presenting complaint.
The distinction from lethargy is that lethargy is specifically about energy, whereas malaise is a broader sense of wrongness.
Why it matters
Persistent malaise deserves a structured assessment rather than reassurance — a history, an examination and baseline blood tests will identify a treatable cause in a substantial proportion of cases.
Malaise with unexplained weight loss, night sweats, or a fever lasting more than a week warrants prompt assessment.
Clinically reviewed by Dr Mohammad Zubair Khan, GMC 7563469
Last reviewed
August 30, 2026