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FDA Moves to Prevent Serious Adverse Reactions to Alosetron

Cheryl A. Thompson

Rare, serious adverse reactions to alosetron, a drug used to treat the diarrhea-predominant form of irritable bowel syndrome, led the Food and Drug Administration (FDA) to develop patient labeling that must accompany all Lotronex prescriptions dispensed by pharmacies, the agency announced Thursday.

This action comes in response to 15 reports of serious complications during the first four months that Lotronex has been available in the United States, FDA said during a telephone conference. Seven patients had serious complications of constipation, and eight patients had ischemic colitis. Ten of these patients had to be hospitalized. 

"We have received numerous reports of adverse events associated with use of the drug" since June 1, said FDA's Victor Raczkowski, M.D. These more recent reports are still under investigation, he said. 

Among the actions taken by FDA and GlaxoWellcome Inc., the drug's manufacturer, are revision of the product labeling and development of a Medication Guide for patients. 

This marks the first Medication Guide, or "MedGuide," authorized by federal regulations requiring the distribution of FDA-approved patient labeling for certain prescription drug products used primarily by outpatients. FDA can require a MedGuide for products that pose a serious and significant harm to the public health. 

The MedGuide for Lotronex explains the serious adverse effects that could develop from taking the drug, describes the symptoms of constipation and ischemic colitis, and notes which patients should not take the drug. 

Future shipments of Lotronex will include a MedGuide attached to every bottle. Raczkowski said that the product will now be available only in containers of 60 tablets, matching a 30-day supply. The FDA-approved dosage is one tablet taken twice daily. 

Although irritable bowel syndrome is typically first diagnosed and treated in outpatients, hospital pharmacists should not assume that newly admitted patients have seen the MedGuide, said William L. Greene, Pharm.D., BCPS, FASHP, associate director for clinical pharmacy services at Methodist Healthcare–Central Hospital in Memphis. "The education [about the serious reactions] is still needed." 

And that need for education applies to physicians and nurses, too. Greene suggested that hospital pharmacists ensure the medical and nursing staffs know about the new information and warnings. Posting information on bulletin boards in the medical staff lounges and discussing the issue at key meetings, such as pharmacy and therapeutics committee meetings, are two ideas he offered. Pharmacists could also place educational sheets in the "progress notes" section of patients' charts or call prescribers about each new Lotronex order. 

ASHP Clinical Affairs Associate Cynthia L. LaCivita, Pharm.D., said, "I think it is important that hospital pharmacists act proactively in providing patients with new information on the safety of this drug....We want to prevent any unnecessary adverse drug reactions." Pharmacists should know the contraindications to alosetron therapy and ensure that only appropriate patients receive the drug. 

Kasey K. Thompson, Pharm.D., director of the ASHP Center on Patient Safety concurred. "If possible, pharmacists should provide discharge counseling for patients who have been prescribed Lotronex while in the hospital, ensuring that they understand the risks and benefits of therapy. Patients should know that a pharmacist is available for them to speak to while in the hospital about any concerns or questions about their drug therapy."