ME stands for Myalgic Encephalomyelitis and is also called Chronic Fatigue Syndrome (CFS); it is also sometimes known as ME/CFS. (There is some debate about the name of the illness - it is sometimes referred to as CFS/ME). It is a disease that affects an estimated 250 thousand people in Britain (or 4 in every 1000 people). The most common symptom is a profound, persistent and debilitating malaise, sometimes called fatigue, quite unlike ordinary tiredness or fatigue; it is often made disproportionately worse on exertion, or for some time after exertion.

Other symptoms can include muscle or joint pain, muscle weakness, headaches, sore throat, swollen lymph nodes, dizziness, digestive disorders and memory and concentration problems. There may be over-sensitivity to light, sound and smell. There can also be dysfunction of many other body systems such as temperature regulation, sleep or blood pressure.

ME can affect people to varying degrees, irrespective of lifestyle, age or gender. The type and severity of symptoms varies from person to person. Some people are able to carry on working, while others may be housebound or bed-bound. Some people are able to walk but can't read; and vice-versa. Many people become severely disabled and research has shown that ME can reduce the Quality of Life more than in many other serious illnesses.

Symptoms may also vary from day to day. Managing these ups and downs by pacing can be helpful, in order to avoid overdoing things and then “crashing”.

There is no immediate cure for ME although complete or partial recovery is common.