Alosetron-New Drug for Irritable Bowel (cont.)

Alosetron is expected to be widely-used since IBS is among the ten most commonly diagnosed medical problems, and there are few if any effective treatments. Nevertheless, among women with IBS, diarrhea without constipation (as experienced by the studies' patients) is present in only a minority. Constipation is the most common form of IBS, and alosetron may make constipation worse. Therefore, alosetron is appropriate for only a minority of women with IBS. Alosetron has not been studied in large numbers of men and is not approved or recommended for men because smaller studies showed that it had no benefit among men.

Despite the caveats, alosetron represents an important step forward in the treatment of IBS. The demonstration of its efficacy is likely to spur further research with other drugs that alter the release of chemical messengers or block receptors in the intestine. Progress will come slowly, however, because of the lack of understanding of the cause of IBS.

Last Editorial Review: 7/23/2002