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Fibromyalgia-associated syndromes

It is not unusual for FM patients to have an array of bodily complaints other than musculoskeletal pain. It is now thought that these symptoms are a result of the abnormal sensory processing as described in the previous section. Recognition and treatment of these associated problems are important in the overall management of your FM.

  • Chronic fatigue
  • Restless Leg Syndrome
  • Irritable Bowel Syndrome
  • Irritable bladder syndrome
  • Cognitive dysfunction
  • Cold intolerance
  • Multiple Sensitivities
  • Dizziness
  • Neurally Mediated Hypotension
  • Non-restorative sleep (above)

1. Chronic fatigue—The common treatable causes of chronic fatigue in FM patients are: (1) inappropriate dosing of medications (TCAs, drugs with antihistamine actions, benzodiazepines etc.); (2) depression; (3) aerobic deconditioning; (4) a primary sleep disorder (e.g. sleep apnea); (5) non-restorative sleep (see above); and (6) neurally mediated hypotension. A new drug called Provigil is of some help when used intermittently for management of fatigue.

2. Restless leg syndrome—This strictly refers to daytime (usually maximal in the evening) symptoms of (1) unusual sensations in the lower limbs (but can occur in arms or even scalp) that are often described as paresthesia (numbness, tingling, itching, muscle crawling); and (2) a restlessness, in that stretching or walking eases the sensory symptoms. This daytime symptomatology is nearly always accompanied by a sleep disorder—now referred to as periodic limb movement disorder (formerly nocturnal myoclonus). Treatment is simple and very effective—DOPA / Levodopa (Sinemet) in an early evening dose of 10/100 (a minority require a higher dose or use of the long acting preparations).

3. Irritable bowel syndrome—This common syndrome of GI distress that occurs in about 20% of the general population is found in about 60% of FM patients. The symptoms are those of abdominal pain, distension with an altered bowel habit (constipation, diarrhea or an alternating disturbance). Typically the abdominal discomfort is improved by bowel evacuation. Due to abnormal sensory processing these symptoms may be quite distressing to FM patients. Treatment involves (1) elimination of foods that aggravate symptoms; (2) minimizing psychological distress; (3) adhering to basic rules for maintaining a regular bowel habit; (4) prescribing medications for specific symptoms; constipation (stool softener, fiber supplementation and gentle laxatives such as bisacodyl), diarrhea (loperamide or diphenoxylate) and antispasmodics (dicyclomine or anticholinergic /sedative preparations such as Donnatal).

4. Irritable bladder syndrome—This is found in 40-60% of FM patients. The initial incorrect diagnoses are usually recurrent urinary tract infections, interstitial cystitis or a gynecological condition. Once these possibilities have been ruled out a diagnosis of irritable bladder syndrome (also called female urethral syndrome) should be considered. The typical symptoms are those of suprapubic discomfort with an urgency to void, often accompanied by frequency and dysuria. In a sub-population of FM patients this is related to a myofascial trigger point in the pubic insertion of the rectus abdominus muscles and may be helped by a procaine myofascial trigger point injection. Treatment involves: (1) increasing intake of water; (2) avoiding bladder irritants such as fruit juices (especially cranberry); (3) pelvic floor exercises (e.g. Kegel exercises); and (4) the prescription of antispasmodic medications (e.g. oxybutinin, flavoxate, hyoscamine).

5. Cognitive dysfunction—This is a common problem for many FM patients. It adversely affects the ability to be competitively employed and may cause concern as to an early dementing type of neurodegenerative disease. In practice the latter concern has never been a problem and patients can be reassured. The cause of poor memory and problems with concentration is, in most patients, related to the distracting effects of chronic pain and mental fatigue. Thus the effective treatment of cognitive dysfunction in FM is dependent on the successful management of the other symptoms.

6. Cold intolerance—About 30% of FM patients complain of cold intolerance. In most cases this amounts to needing warmer clothing or turning up the heat in their homes. Some patients develop a true primary Raynaud's phenomenon (which may mislead an unknowing physician to consider diagnoses such as Lupus (SLE) or scleroderma). Many FM patients have cold hands and feet, and some have cutis marmorata (a lace like pattern of purple discoloration of their extremities on cold exposure). Treatment involves: (1) keeping warm; (2) low-grade aerobic exercise (which improves peripheral circulation); (3) treatment of neurally-mediated hypotension; and (4) the prescription of vasodilators such as the calcium channel blockers (but these may aggravate the problem in patients with hypotension).

7. Multiple sensitivities—One result of disordered sensory processing is that many sensations are amplified in FM patients. In general FM patients are less tolerant of adverse weather, loud noises, bright lights and other sensory overloads. Treatment involves being aware that this is an FM-related problem and employing avoidance tactics.

8. Dizziness—This is a common complaint of FM patients. Before this symptom is attributable to FM a thorough evaluation for other neurological causes should be pursued (e.g. postural vertigo, vestibular disorders, 8th nerve tumors, demyelinating disorders, brain stem ischemia and cervical myelopathy). In many cases no obvious cause is found, despite sophisticated testing. Treatable causes related to FM include: (1) proprioceptive (awareness of posture, movement, changes in equilibrium) dysfunction secondary to muscle deconditioning; (2) proprioceptive dysfunction secondary to myofascial trigger points in the sterno-cleido-mastoids and other neck muscles; (3) neurally mediated hypotension (see below); and (4) medication side effects. Treatment is dependent on making an accurate diagnosis. In patients in whom no obvious cause is found a trial of physical therapy, concentrating on proprioceptive awareness may prove worthwhile relief.

9. Neurally mediated hypotension—Patients with this problem usually have a low blood pressure that does not go up normally on standing or on exercise. Although such patients often have a low ambient BP with postural changes, these findings are not a prerequisite for diagnosis. A tilt table test (sometimes with the infusion of isproterenol) is the most reliable way to confirm this diagnosis. Treatment involves: (1) education as to the triggering factors and their avoidance; (2) increasing plasma volume (increased salt intake, prescription of florinef); (3) avoidance of drugs that aggravate hypotension (e.g. TCA's, anti-hypertensives); (4) prevent the involuntary response (prescribe beta-adrenergic antagonists e.g. propranolol (inderal) or metoprolol (lopressor) or disopyramide (norpace), but these agents are only used as a last resort because they reduce exercise tolerance); and (5) minimize the efferent limb of the involuntary response (prescribe alpha-adrenergic agonists e.g. midodrine (proamatine) or anti-cholinergic agents.


Dr. Bennett is an internationally known FM specialist, Professor of Medicine at Oregon Health Sciences University (OHSU), and Chairman of Arthritis and Rheumatic Diseases Division.  Permission was granted to publish this article from the Oregon Fibromyalgia Foundation's website: © 2002 Robert Bennett M.D., FRCP.