Optimizing outcomes with alosetron hydrochloride in severe diarrhea-predominant irritable bowel syndrome

Irritable bowel syndrome (IBS) is a highly prevalent functional gastrointestinal disorder that causes a range of symptoms. Currently, alosetron hydrochloride (Lotronex®), a selective serotonin type 3 receptor antagonist, is the only medication approved for the treatment of severe diarrhea-predominant irritable bowel syndrome (IBS-D) in women who have inadequately responded to conventional therapy. Alosetron has demonstrated efficacy compared with placebo in clinical trials and has been shown to improve overall health-related quality of life (HRQoL). However, rare instances of ischemic colitis and severe complications of constipation have been reported. As a result, in 2000 alosetron was voluntarily withdrawn from the market but was reintroduced in 2002 with a more restricted indication and a requirement that clinicians and patients follow a prescribing program. Although the efficacy and benefit of alosetron has been clearly demonstrated, it has been used sparingly since its reintroduction. This brief review describes the history of alosetron, efficacy of alosetron in the treatment of IBS, the impact of severe IBS on HRQoL, safety considerations, the risk evaluation and mitigation strategy program under which alosetron is now prescribed, and an update on postmarketing surveillance data.