What are the symptoms of chronic fatigue syndrome?

The tiredness is more than ordinary sleepiness and may not improve after rest. Activity can trigger a delayed flare of exhaustion, dizziness, flu-like feelings, pain or difficulty thinking. Sleep may be disrupted or leave you feeling as tired on waking as before bed. Some people also notice headaches, muscle or joint pain, sensitivity to light or sound, and feeling worse when upright. These symptoms can overlap with fatigue, low mood, glandular fever and other conditions, so the pattern matters more than any single symptom.

Keep a simple record of sleep, activity, symptoms and delayed flares. Arrange a GP Consultation if symptoms persist, limit work or study, or keep returning. A clinician may review your history, examine you and use a Blood Test or other checks to look for alternative explanations. Avoid pushing through a flare; gentle pacing, regular fluids, planned rest and adjusting activity to your current energy can reduce setbacks.

Seek urgent medical help for new severe breathlessness, chest pain, fainting, sudden weakness, confusion, or thoughts of self-harm. Contact a clinician promptly if exhaustion is rapidly worsening, you cannot keep fluids down, or dizziness makes standing unsafe. Persistent fatigue deserves assessment even when symptoms are gradual, because several treatable conditions can resemble this pattern.

Ask which symptoms and delayed reactions support the diagnosis, what alternative causes should be checked, and how to pace activity safely. Ask when to repeat assessment and whether sleep, pain, mood or dizziness needs separate treatment.