What causes chronic fatigue syndrome?

Chronic fatigue syndrome, also called myalgic encephalomyelitis, is considered when substantial exhaustion is accompanied by reduced ability to function and symptoms that worsen after physical or mental effort. Sleep may not feel restorative, and concentration, pain, dizziness, or sensitivity to light and sound can occur. Glandular fever is one infection that may precede the illness, but a previous infection does not prove that it caused an individual's symptoms. Similar symptoms can arise from anaemia, thyroid problems, sleep disorders, medication effects, mood disorders, or other illnesses, so assessment is needed.

Keep a gentle record of energy, sleep, symptoms, and activity so patterns are visible without pushing yourself to exhaustion. Plan essential tasks around available energy, take regular rest, and avoid sudden increases in exercise. A clinician can review your history, examine you, and arrange tests to look for other explanations. Treatment is usually shaped around the person's symptoms, such as sleep difficulties, pain, dizziness, or limits after exertion. Be cautious of products that promise a universal cure.

Arrange medical review for ongoing fatigue that limits work, study, self-care, or normal activity, especially after an infection. Seek urgent help for chest pain, severe breathing difficulty, fainting, new weakness on one side, confusion, inability to keep fluids down, or thoughts of self-harm. A sudden change from your usual symptoms should be assessed rather than attributed automatically to chronic fatigue syndrome.

Ask which alternative causes should be checked, whether your symptoms fit post-exertional worsening, and how to pace daily activity. Discuss sleep, pain, dizziness, work adjustments, and which warning signs require prompt reassessment.