Liver Injuries Linked to Use of Popular Diet Drug Prompts FDA

Health risks gained may outweigh pounds lost by using weight loss drug orlistat. The U.S. Food and Drug Administration (FDA) has issued an Early Communication regarding an ongoing safety review of the drug after receiving a total of 32 reports of serious liver injury in patients taking orlistat.

The review of adverse events reported between 1999 and 2008 involves marketed name brands of orlistat that include the over the counter drug Alli, and the prescription drug Xenical. Of the 32 cases of liver injury reported, 27 required hospitalization, with six resulting in liver failure. Only two of the reported cases occurred within the United States. Symptoms of liver injury, including jaundice-related yellowing of the skin or whites of the eyes, weakness, and stomach pain, were among the most common adverse effects reported in association with the use of orlistat.

The FDA is also reviewing data on suspected cases of liver injury that have been submitted by manufacturers of orlistat. The health issues that are apparently linked to the drug were a topic of discussion for the FDA’s Center for Drug Evaluation and Research Drug Safety Oversight Board in April of this year. According to Steven Osborne, M.D., executive director of the board, “The issues here are complex, but FDA has benefited from the input of the Board, including comments from representatives from three FDA Centers and several other Agencies in the Department of Health and Human Services.”

Orlistat works by blocking the absorption of ingested dietary fats. The FDA approved Xenical (orlistat 120mg) as a prescription product in 1999 for the purpose of obesity management, to be taken in conjunction with a reduced caloric diet. The over-the-counter version, orlistat 60 mg, was approved for use by overweight adults ages 18 and older in 2007, although first year sales did not reach the manufacturer’s projection. According to the FDA, orlistat is currently approved for marketing in 100 countries worldwide.

At this time, no defined association has been determined between the use of orlistat and liver injury, and it has not been deemed unsafe for patients who take Xenical as prescribed, or Alli as directed, to continue to do so. In addition, the FDA is not advising healthcare professionals to change their prescribing practices regarding orlistat.

The FDA uses the Early Communication tool to inform the public of ongoing safety reviews of drugs. Upon completion of the review, the FDA will release its findings on orlistat. Meanwhile, the FDA advises consumers taking the drug, as well as those who have used it in the past, to consult a healthcare professional if they experience symptoms that could possibly be related to liver injury. Symptoms may include weakness or fatigue, fever, jaundice, brown urine, abdominal pain, nausea, vomiting, light-colored stools, itching, or loss of appetite.

The FDA is also urging consumers and healthcare professionals alike to report all suspected side effects associated with the use of orlistat to the FDA MedWatch Adverse Event Reporting program. Reports can be made online, or by calling 800-FDA-1088. Reports may also be sent by printing FDA form 3500, filling out the form and faxing it to 800-FDA-0178, or mailing the postage paid form to MedWatch, 5600 Fishers Lane, Rockville, MD 20852-9787.