The chronic fatigue syndrome (CFS) is characterized by an intense fatigue state, which is not relieved by bed rest, has duration of at least 6 months and is responsible for impairment of the subjects capacity of fulfilling daily activities. The diagnosis is difficult because besides fatigue, the syndrome associates symptoms common for many other diseases, such as - muscle pain, memory and concentration disorders, headaches, multiple joint pain, sleep disorders, tender lymph nodes. The causes are unknown; the syndrome affects more often the female sex, during the fourth and fifth decades of life. Usually it lasts for years. An important feature is represented by worsening of the symptoms after intense physical or mental activity, lasting for more than 24 hours. Although this does not cover the whole polymorphism of the syndrome, in 1994 two diagnostic criteria were established: 1. extreme fatigue, lasting for at least 6 months, without other medical condition; 2. at least 4 of the following symptoms: severe impairment of short term memory and/or of the concentration capacity; muscle pain; multiple joint pain; sore throat; unresting sleep; headaches displaying a new pattern or severity; tender lymph nodes; post-exertional fatigue, lasting more than 24 hours. More than one million people were diagnosed with the syndrome in the USA, but tens of millions of people have similar syndromes, without fully satisfying the diagnosis criteria. It is estimated that only 20% of the cases are diagnosed. CFS may be as disabling as multiple sclerosis, lupus, rheumatoid arthritis, congestive heart failure, etc. Although a cause hasnt been isolated yet, possible etiologies include viral infections, stress and exposure to toxins. Immune data did not reveal immune factors involved in the genesis of the syndrome, besides a predisposition to developing allergic reactions. The hypothalamus-pituitary-adrenal axis showed no changes useful for diagnosis or therapy. Overlapping CFS and neurally mediated hypotension were investigated with no results in treating all cases. The syndrome shows a cyclic evolution with remission and relapse periods. After the apparent recovery, a relapse is usual. The earlier the diagnosis and therapy initiation, the better the chances of full and rapid recovery. The therapy targets each patients symptoms - pain, sleep disorders, memory and concentration problems. Many patients may overreact to medication, especially to sedatives. Usually, the therapeutic benefits are obtained with lower doses than usual. The medications side effects may aggravate the symptoms of the syndrome. The patients usually display high sensitivity to caffeine, alcohol and nicotine. Alternative therapies, such as acupuncture, massage, yoga are used for relieving the symptoms. There is need for more studies focused on the causes of the chronic fatigue syndrome.read more..