There's no test for myalgic encephalomyelitis or chronic fatigue syndrome (ME/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.

They may also offer you tests like blood tests or urine tests to rule out other conditions, such as anaemia (lack of red blood cells), an underactive thyroid gland, or liver and kidney problems.

It can take a while for ME/CFS 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 from the National Institute for Health and Care Excellence (NICE) say doctors should consider diagnosing ME/CFS 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
• headaches
• 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 ME/CFS, they may be referred to a paediatrician.

As the symptoms of ME/CFS are similar to those of many common illnesses that usually get better on their own, a diagnosis of ME/CFS 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 3 months.