What should you know about fuzzy head and tiredness?

Mental fog may feel like slowed thinking, poor concentration or difficulty finding words. Tiredness can follow disrupted sleep, emotional strain, dehydration, a viral illness, medication effects or missed meals. Ongoing symptoms may also occur with anaemia, coeliac disease, kidney disease, burnout or chronic fatigue syndrome. Alcohol use can worsen sleep quality and concentration, while COVID-19 may cause fatigue during or after infection. These possibilities overlap, so one symptom alone cannot identify the cause.

Keep a short record of sleep, meals, fluids, medicines, alcohol, stress, menstrual bleeding and the times when the fog is strongest. Regular meals, gentle activity, a consistent sleep routine and adequate fluids may help when lifestyle factors are contributing. Arrange a medical review if symptoms persist, interfere with work or driving, recur without a clear trigger, or come with weight change, paleness, thirst, bowel changes or low mood. A clinician may examine you and choose blood or urine tests based on your history.

Seek emergency help for sudden confusion, trouble speaking, one-sided weakness, a new severe headache, fainting, chest pain or severe breathing difficulty. Get prompt advice for confusion with fever, repeated vomiting, inability to keep fluids down or rapidly worsening drowsiness.

Ask whether your medicines, sleep pattern or recent illness could contribute, which examinations or tests are appropriate, and whether you should avoid driving while concentration is impaired.