Myalgic encephalomyelitis, also called chronic fatigue syndrome or ME/CFS, is a long-term condition with a wide range of symptoms. The most common symptom is extreme tiredness.

ME/CFS can affect anyone, including children. It's more common in women, and tends to develop between your mid-20s and mid-40s.

Symptoms of ME/CFS

Feeling extremely tired all the time – you may find it very hard to do daily activities
Still feeling tired after resting or sleeping
Taking a long time to recover after physical activity
Problems sleeping, such as waking up often during the night
Problems with thinking, memory and concentration

Some people with ME/CFS may also have other symptoms, including:

Muscle or joint pain
Headaches
A sore throat
Flu-like symptoms
Feeling dizzy or sick
Fast or irregular heartbeats (heart palpitations)