In 2006, the consumer advocacy group Public Citizen petitioned the FDA to remove Xenical from the U.S. market, not because of liver-related issues but because it might increase the risk of aberrant crypt foci, believed to be precursors to colon cancer.
The FDA's approval of the first over-the-counter drug for weight loss came as the United States and other western nations are struggling with an unprecedented obesity epidemic.
According to the U.S. National Center for Health Statistics, 30 percent of American adults aged 20 and older -- more than 60 million people -- are obese. Another 36 percent are considered overweight.
Orlistat is also approved in some 100 countries, with an over-the-counter form available in the European Union.
The U.S. National Library of Medicine has more on orlistat.
SOURCES: Eugene Schiff, M.D., professor, medicine, and director, Center for Liver Diseases, University of Miami Miller School of Medicine; Timothy Pfanner, M.D., assistant professor, internal medicine, Texas A&M Health Science Center College of Medicine, and gastroenterologist, Scott & White; Aug. 24, 2009, news release, U.S. Food and Drug Administration