United States of America - The Food and Drug Administration (FDA) has developed a Medication Guide for distribution by pharmacists to help ensure that patients using the prescription drug alosetron hydrochloride (Lotronex®) for treatment of the diarrhoea-predominant form of irritable bowel syndrome will understand the rare but serious risks and how they can take action. Risks include complications from constipation and the risk of ischemic colitis, caused by reduced blood flow to the intestines.

Irritable bowel syndrome is a functional abnormality of the gastrointestinal tract that is estimated to affect up to 15% of the US population. People with this condition experience chronic or recurrent abdominal pain and irregular bowel movements. This condition is two to three times more common in women than men.

Prescribing information has also been updated. This states that treatment should not be started when women are constipated and it informs pre-scribers that alosetron hydrochloride is now contraindicated in women with:

• A history of intestinal obstruction, stricture, toxic megacolon, gastrointestinal perforations, and/or adhesions or ischemic colitis;

• Active diverticulitis; or

• Current Crohn's Disease or ulcerative colitis, or a history of such a disease.

Reference: HHS News, P00-17 (2000).