All questions about ME/CFS and long COVID

How is it diagnosed?

There's no test. Other conditions are ruled out with blood and urine tests, and ME/CFS is diagnosed when the core symptoms have lasted at least three months and nothing else explains them.

It can take a while, because conditions such as anaemia or an underactive thyroid need ruling out first. Adults should be referred to a specialist ME/CFS team to confirm the diagnosis and make a care plan.

Sources

• NHS: ME/CFS, diagnosis
• ME Association: What are ME/CFS and long COVID? (summarises the NICE 2021 guideline)

Reviewed 2026-11-09 · next review 2027-11-09