FDA Reviewing Safety Profile of Popular Weight Loss Products

Another weight loss drug has come under FDA scrutiny.

The agency said Aug. 24 that it is reviewing the safety of orlistat after receiving reports of liver injury in patients using the drug, which is marketed as the prescription drug Xenical and the OTC medication Alli.

FDA officials said the review is ongoing, and no definite association between liver injury and orlistat has been established. Physicians and consumers should report side effects associated with the use of orlistat products to the MedWatch adverse events reporting program.

Xenical (120 mg orlistat), which is manufactured by Roche Pharmaceuticals, received FDA approval in 1999 for obesity management in conjunction with a reduced caloric intake; the drug also is indicated to reduce the risk of regaining weight after previous weight loss. In 2007, the FDA approved Alli (60 mg orlistat), which is manufactured by GlaxoSmithKline, for OTC use for weight loss in overweight adults in conjunction with a reduced-calorie and low-fat diet.

The FDA said that between 1999 and October 2008, it received 32 reports of serious liver injury in patients taking orlistat. Twenty-seven patients required hospitalization, and six cases resulted in liver failure.

Overall, the most commonly reported adverse events associated with orlistat use are jaundice, weakness and stomach pain. Other possible side effects include abdominal pain, nausea, vomiting, light-colored stools, itching and loss of appetite.

More than 100 countries worldwide have approved the use of orlistat products, and the vast majority of adverse events reported have occurred outside the United States. The FDA said that in addition to the 32 reported cases of serious liver damage, it is reviewing other data on suspected cases of liver injury submitted by the manufacturers of orlistat products.

The FDA is not advising physicians to change their prescribing practices at this time. The agency also said that consumers taking Xenical should continue to take it as prescribed, and those using Alli also should continue to use the product as directed.