On May 26, 2010, the Food and Drug Administration notified health care professionals of its order to revise the warning labels of the weight loss medications containing orlistat. Orlistat is the active ingredient found in the prescription drug, Xenical, which contains 120 mg of orlistat, and in the over- the- counter drug, Alli, which contains 60 mg of orlistat. The FDA initially announced in August 2009 concern of possible liver damage caused by orlistat. Following a complete review, the FDA has approved a revised label for Xenical to include safety information. This additional information addresses the reports of rare cases of severe liver injury associated with the use of orlistat.
The FDA reviewed data from preclinical and clinical trials of the drugs, post marketing studies, and use of the drugs among the general public from April 1999 to August 7, 2009. During this period, an estimated 40 million people worldwide used Xenical or Alli. One reported U.S. case of Alli use and 13 reported foreign cases of Xenical use were associated with severe liver injury. Of these cases, two people died of liver failure and three individuals required liver transplants. The FDA pointed out that some of these individuals were taking other medications and had medical conditions that may have impacted the development of severe liver damage.
The FDA cautioned that the correlation between orlistat and severe liver injury has not been established. The action to revise the information labels of Xenical and Alli is intended to educate the public of the possibility of this side effect. Patients are advised to stop taking Xenical or Alli and notify their physicians if any of the following symptoms develop.The symptoms of liver injury are itching, yellow color of the skin and the whites of the eyes, dark urine, light-colored stools, and loss of appetite.