Irritable bowel syndrome: a mild disorder; purely symptomatic treatment.

(1) Patients frequently complain of occasional bowel movement disorders, associated with abdominal pain or discomfort, but they are rarely due to an underlying organ involvement. Even when patients have recurrent symptoms, serious disorders are no more frequent in these patients than in the general population, unless other manifestations, anaemia, or an inflammatory syndrome is also present; (2) There is currently no way of radically modifying the natural course of recurrent irritable bowel syndrome; (3) The effects of antispasmodics on abdominal pain have been tested in about 20 randomised controlled trials. Pinaverium and peppermint essential oil have the best-documented efficacy and only moderate adverse effects. Antispasmodics with marked atropinic effects do not have a favourable risk-benefit balance; (4) Tricylic antidepressants seem to have only modest analgesic effects in this setting. In contrast, their adverse effects are frequent and they have somewhat negative risk-benefit balances. Nor has the efficacy of selective serotonin reuptake inhibitor antidepressants (SSRIs) been demonstrated; (5) Alosetron and tegaserod carry a risk of potentially life-threatening adverse effects and therefore have negative risk-benefit balances; (6) Seeds of plants such as psyllium and ispaghul, as well as raw apples and pears, have a limited impact on constipation and pain. Osmotic laxatives are effective on constipation. Symptomatic treatments for constipation can sometimes aggravate abdominal discomfort; (7) Loperamide has been poorly assessed in patients with recurrent irritable bowel syndrome with diarrhoea. It modestly slows bowel movement but does not relieve pain or abdominal discomfort; (8) Dietary measures have not been tested in comparative trials. Some patients are convinced that certain foods provoke a recurrence of irritable bowel syndrome, but restrictive diets carry a risk of nutritional deficiencies; (9) Various techniques intended to control emotional and psychological disturbances have been proposed, including relaxation, biofeedback, hypnosis, and psychotherapy. The results of clinical trials are not convincing; (10) Oral products containing live bacteria, designed to change the equilibrium of intestinal flora, have been tested in 13 placebo-controlled trials, with inconsistent results. A few cases of septicaemia have been reported; (11) The six available trials of acupuncture (versus sham acupuncture) showed no more than a placebo effect; (12) In practice, patients who have recurrent irritable bowel syndrome but with no other signs of a condition warranting specific treatment should be reassured as to the harmless nature of their disorder if a careful physical examination and basic laboratory tests are negative. The only available treatments have purely symptomatic effects and only limited efficacy. It is best to avoid using all treatments and additional diagnostic investigations that carry a risk of disproportionate adverse effects.

Prescrire Int. 2009 Apr;18(100):75-9.