Chronic Fatigue: A Symptom That Deserves a Workup
Persistent fatigue beyond 6 weeks needs evaluation.
Dr. Marc Aubry
Internist
In simple terms
Fatigue is one of the most common reasons for medical consultation. A structured approach finds the cause in most cases.
What you need to remember
- Common reversible causes — Iron deficiency, hypothyroidism, sleep apnoea, depression, medication side effects, alcohol excess, untreated chronic disease.
- When to think ME/CFS — Severe fatigue >6 months, post-exertional malaise, unrefreshing sleep, cognitive difficulties — diagnosis of exclusion.
- Self-care — Regular sleep schedule, balanced meals, gradual physical activity, limit alcohol and screen-time before bed.
Full blood count, ferritin, thyroid function, glucose, liver and kidney function, calcium, vitamin D and B12. Coeliac serology when appropriate.
Common reversible causes
Iron deficiency, hypothyroidism, sleep apnoea, depression, medication side effects, alcohol excess, untreated chronic disease.
When to think ME/CFS
Severe fatigue >6 months, post-exertional malaise, unrefreshing sleep, cognitive difficulties — diagnosis of exclusion.
Self-care
Regular sleep schedule, balanced meals, gradual physical activity, limit alcohol and screen-time before bed.
Fatigue that does not improve with rest deserves medical review rather than another supplement.
The words explained
Medical terms used above, in everyday language.
- Chronic
- A problem that lasts a long time, usually more than three months, and often comes back.
- Diagnosis
- The moment a doctor identifies which illness is causing your symptoms.
- Blood sugar
- The amount of sugar circulating in your blood, your body's main fuel.
- Cognitive
- Related to thinking: memory, attention, learning and decision-making.
When should you see a doctor?
- Your symptoms last more than a few weeks or keep coming back.
- They get worse quickly, or stop you doing everyday things.
- You notice sudden pain, breathing trouble, fainting or bleeding — seek urgent care.
- You already take medication and want to change anything about it.
This article explains general health information. It does not replace advice from your own doctor.
Frequently asked questions
- What is Chronic Fatigue: A Symptom That Deserves a Workup?
- Fatigue is one of the most common reasons for medical consultation. A structured approach finds the cause in most cases.
- What are the main symptoms or signs of Chronic Fatigue: A Symptom That Deserves a Workup?
- Common signs vary from person to person. The article above lists the symptoms to watch for, how they progress, and when they need medical attention.
- When should you see a doctor for Chronic Fatigue: A Symptom That Deserves a Workup?
- See a doctor if symptoms last more than a few weeks, get worse quickly, stop you doing everyday things, or if you notice sudden pain, breathing trouble, fainting or bleeding.
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