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More Upsetting News About Irritable Bowel Treatment



"We are now trying to learn as much as we can about each of these events," he tells WebMD, adding that some of the recent reports refer to events that happened prior to September, when the consumer pamphlet was released.


For its part, Glaxo Wellcome maintains that the risk of ischemic colitis is minimal and probably not associated with Lotronex. When asked whether there is a possible association, Eric Carter, MD, PhD, director of Glaxo Wellcome's U.S. gastrointestinal drug division, says that after extensive animal and human studies of the drug, the researchers there could not find a mechanism to explain the reports of ischemic colitis.


The majority of events have been temporary and reversible, with less than half of the patients requiring hospitalization, Carter notes. This type of ischemic colitis also has been associated with a number of other medications, including oral contraceptives, he notes.


The reports, Carter adds, may simply reflect the true incidence of ischemic colitis in the U.S. Currently, the estimated incidence is about three out of every 10,000 people, but the temporary ischemic colitis reported in association with Lotronex use "probably occurs more frequently [in the general public] than is recognized," he tells WebMD.


Still, Carter cautions physicians and patients to take the time to determine whether Lotronex truly is the appropriate treatment. Clinical studies have shown Lotronex greatly benefits women, with about 75% reporting a significant improvement in their symptoms over 12 months, but the drug is not indicated for any men or for women whose predominate IBS symptom is constipation, he tells WebMD.


"It is not the mandate of a pharmaceutical company to tell a physician how to practice medicine. Quite frankly, no one can do that," he says. But while the company is reluctant to question the clinical judgement of physicians, the recent reports do demonstrate that the drug is being prescribed inappropriately to some patients, including patients with a history of severe intestinal disease, he tells WebMD.


To address this particular issue, the company is launching an advertising campaign aimed at consumers to help them determine whether Lotronex is appropriate for them. Despite Glaxo's actions, the controversy surrounding Lotronex is unlikely to die anytime soon.


Because IBS is a difficult condition to diagnose, it is possible that a number of the patients prescribed Lotronex do not even have the condition, Public Citizen says. "We don't think it should have been approved in the first place," Larry Sasich, PharmD, MPH, the group's lead researcher, noted in a recent interview with WebMD.


About 70-80% of patients prescribed Lotronex potentially are being exposed to the risk of ischemic colitis without enjoying any medical benefit, FDA officials also noted previously. This figure comes from clinical trials, which indicate that about 80% of the people who participated in the trials either failed to improve or improved due to other reasons, said Florence Houn, MD, director of the FDA's office responsible for intestinal drugs.

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