What should you know about post viral fatigue?

The immune response, disrupted sleep, reduced activity, poor appetite, and dehydration can leave the body feeling drained after a virus. Fatigue may affect concentration, memory, mood, and tolerance for exercise. COVID-19 can be followed by prolonged symptoms, but other illnesses can do this too. Anaemia, kidney disease, coeliac disease, alcohol-related problems, burnout, or chronic fatigue syndrome may need consideration when tiredness is marked, persistent, or accompanied by other symptoms. Fatigue itself does not identify one diagnosis.

Break tasks into smaller parts and alternate activity with rest before you are exhausted. Increase activity slowly rather than forcing a return to your previous level. Keep regular meals, drink enough to avoid dehydration, and use a consistent sleep routine. Track what worsens symptoms, including delayed exhaustion after exertion. Ask for practical help with work or household duties while you recover, and avoid relying on alcohol to sleep or relax.

Arrange an appointment if fatigue persists, worsens, follows even light activity with a delayed crash, or prevents work, washing, eating, or other daily needs. Seek urgent help for chest pain, severe breathlessness, fainting, new confusion, one-sided weakness, or inability to keep fluids down. A clinician can review your illness, medicines, sleep, mood, diet, and possible tests.

Ask which symptoms suggest another cause, whether blood or other tests are appropriate, how to pace activity, and how to plan a safe return to work or exercise.