What should you know about cortisol fatigue?

Cortisol helps regulate the stress response, blood pressure, metabolism, and the sleep-wake rhythm. Its levels change naturally and can be influenced by illness, disrupted sleep, steroid medicines, and ongoing stress. “Adrenal fatigue” is not a recognised explanation for every episode of tiredness, and commercial hormone tests may be difficult to interpret.

Low energy can accompany anaemia, dehydration, infection, kidney disease, digestive conditions, burnout, alcohol-related problems, or chronic fatigue syndrome. The pattern matters: note whether rest helps, how long symptoms have lasted, and whether there is weight change, pain, fever, breathlessness, or low mood.

Keep a brief record of sleep, activity, meals, symptoms, and medicines. Aim for a regular sleep routine, gentle activity within your limits, balanced meals, and enough fluids. Avoid unregulated cortisol supplements and do not change steroid treatment without medical advice.

Book a GP appointment when fatigue persists, keeps returning, or limits work, study, caring, or exercise. The clinician may examine you and choose tests based on your history rather than ordering cortisol automatically.

Seek urgent help for fainting, confusion, severe weakness, trouble breathing, chest pain, inability to keep fluids down, or signs of severe dehydration. These symptoms need immediate assessment.

Arrange prompt care for fatigue with unexplained bleeding, persistent fever, rapidly worsening illness, major mood changes, or thoughts of self-harm. Tell the clinician about all steroid medicines and recent infections.

Ask which causes fit your symptom pattern, whether blood tests or a cortisol test are appropriate, how activity should be paced, and when worsening fatigue should be reviewed.