FDA Warns of Xenical, Alli Liver Problems Following Worldwide Reports

The FDA is requiring new warnings about the risk of liver damage from Alli and Xenical after the two popular diet drugs have been linked to reports of death and liver failure. 

The FDA issued an early communication last August indicating that they were investigating reports of Xenical and Alli liver damage. In a follow up drug safety communication issued Thursday, the agency indicates that at least 13 cases of severe liver injury from Alli and Xenical have been found, including at least two cases where patients died and three where a liver transplant was needed.

Xenical (orlistat 120mg) is a prescription medication that was approved by the FDA in 1999. The lower dose Alli (orlistat 60mg) is an over-the-counter weight-loss drug that was approved in 2007. Both drugs are marketed by GlaxoSmithKline, PLC, though Xenical is manufactured by Roche.

The medications are intended for use together with a reduced-calorie diet. They work by preventing the absorption of fats, thereby reducing caloric intake. In 2008, Xenical generated sales of $30 million and Alli generated sales of $131 million during its first full year on the market.

The new label changes will warn of rare cases of severe liver injury, and indicate that healthcare professionals and consumers should watch for symptoms of liver injury, including:

• Itching yellow eyes or skin
• Dark urine
• Light-colored stools
• Loss of appetite

Patients should stop using the drugs and contact their healthcare professional if these symptoms develop.

The FDA notes that an estimated 40 million individuals have used the medications, and only one of the reports of liver problems were found in the United States, involving a user of Alli. The remaining 12 cases occurred outside the United States, and involved liver problems with Xenical. There has been no direct causal relationship established between the two orlistat-based drugs and liver injury.

The primary known side effects of Alli and Xenical include oily and loose stools, fecal incontinence, frequent or urgent bowel movements and flatulence, which tend to be most severe when the treatment is started and may decrease with time.

There have been suggestions that orlistat could increase the risk of colon cancer and breast cancer, and the consumer advocacy group Public Citizen has called for an Xenical recall since 2006.