Sufferers feel as if they are recovering from a severe bout of flu. Because of this, it is associated with chronic fatigue syndrome (CFS), and appears to affect more women than men.

Most sufferers also have the ‘alpha-EEG anomaly’, where they fall asleep easily, but deeper sleep is interrupted by waking-state brain activity. Irritable bowel symptoms, including constipation, diarrhoea, abdominal pain and gas, and nausea are experienced by up to 70 per cent of sufferers. Severe-to-moderate jaw pain - or temporomandibular joint dysfunction syndrome - and chronic headaches affect 50-75 per cent. Other complaints are poor memory/concentration, mood swings and dry eyes/mouth.

Although the cause is uncertain, speculative suggestions range from a viral/bacterial infection, accident trauma or another disorder such as lupus or rheumatoid arthritis. The Pill has also been blamed (Dig Chiroprac Econ, 1991; 34: 100-1), and four women who had fibromyalgia for up to 17 years had an almost immediate remission in symptoms when MSG was removed from their diets (Ann Pharmacother, 2001; 35: 702-6).

But a credible body of research links the condition to the thyroid. It was found that virtually all sufferers have altered hormonal feedback mechanisms (Scand J Rheumatol Suppl, 2000; 11: 8-12). Other studies concur, finding hypothyroidism to be a common factor (J Rheumatol, 1992; 19: 121-2; 1993; 20: 469-74). A similar theory is the basis of Dr John Lowe’s book, The Metabolic Treatment of Fibromyalgia (Lafayette, CO: McDowell Publishing, 2000).

What doctors tell you Many doctors still consider fibromyalgia and its cousin, chronic fatigue, to be mainly ‘all in the head’ of hysterical women, even though the World Health Organization has recognised them as genuine conditions.

Physicians who do treat fibromyalgia sympathetically may first try to establish a deep and undisturbed sleep pattern, using medications to boost serotonin and norepinephrine, the neurotransmitters that modulate sleep, pain and immune function. These may be prescribed in low doses, and include amitriptyline, cyclobenzaprine and citalopram. Sleeping pills that may be prescribed include clonazepam and trazodone.

To treat the muscle pain, drugs such as the opioid analgesic tramadol - but, more often, a powerful painkiller, probably one from the family of NSAIDs (non-steroidal anti-inflammatory drugs) - may be prescribed, along with muscle relaxants such as Valium.

Bryan Hubbard