There's no test for chronic fatigue syndrome (CFS), but there are clear guidelines to help doctors diagnose the condition.
A GP should ask you about your medical history and give you a physical examination.
It can take a while for CFS/ME to be diagnosed because other conditions with similar symptoms need to be ruled out first.
In the meantime, you may be given some advice about managing your symptoms.
Guidelines for diagnosing CFS/ME
Guidelines from the National Institute for Health and Care Excellence (NICE) say doctors should consider diagnosing CFS/ME if a patient has extreme tiredness that cannot be explained by other causes and the tiredness:
- started recently, has lasted a long time, or keeps coming back
- means you cannot do the things you used to do
- gets worse after activity or gentle exercise, such as a short walk
You must also have some of these symptoms:
- problems sleeping, such as insomnia
- muscle or joint pain
- a sore throat or sore glands that are not swollen
- problems thinking, remembering or concentrating
- flu-like symptoms
- feeling dizzy or sick
- fast or irregular heartbeats (heart palpitations)
- doing exercise or concentrating makes your symptoms worse
The GP should consult a specialist if they're unsure about the diagnosis or if you have severe symptoms.
If a child or young person under 18 has symptoms of possible CFS/ME, they should be referred to a paediatrician within 6 weeks of first seeing a doctor about their symptoms.
As the symptoms of CFS/ME are similar to those of many common illnesses that usually get better on their own, a diagnosis of CFS/ME may be considered if you do not get better as quickly as expected.
The diagnosis should be confirmed by a doctor after other conditions have been ruled out, and if your symptoms have lasted at least:
- 4 months in an adult
- 3 months in a child or young person
For more detailed information, see the NICE guidelines on how CFS/ME is diagnosed.
Page last reviewed: 29 January 2021
Next review due: 29 January 2024