What should you know about constant fatigue?

Fatigue may be physical tiredness, reduced concentration, low motivation, or a need for more sleep. Anaemia can cause tiredness with pallor, breathlessness, dizziness, or palpitations. Dehydration and COVID-19 may bring fatigue alongside thirst, fever, cough, or body aches. Coeliac disease can affect energy through digestive symptoms and poor nutrient absorption. Chronic kidney disease may cause fatigue with swelling, changes in urination, or nausea. Burnout, alcohol use disorder, and chronic fatigue syndrome have different patterns and need careful assessment rather than a label based on tiredness alone.

Review sleep quality, mood, diet, activity, recent illness, alcohol, and medicines. Fatigue is a symptom, not a diagnosis.

Keep a steady sleep and wake routine, eat regular balanced meals, drink fluids, and use gentle activity within your limits. Note when fatigue began, what worsens it, how you sleep, and any associated symptoms. Avoid increasing caffeine late in the day or using alcohol as a sleep aid. Arrange a clinician review if fatigue persists, limits work or daily care, or cannot be explained by a recent short illness.

Seek urgent help for fatigue with chest pain, severe breathlessness, fainting, new confusion, one-sided weakness, black stools, or thoughts of self-harm. Prompt assessment is appropriate for unexplained weight change, persistent fever, swollen legs, marked thirst, blood loss, or worsening inability to function.

Could sleep, mood, medication, anaemia, infection, nutrition, or kidney function explain this? Which examination or blood tests are appropriate? How can I pace activity while the cause is being assessed?