Consumer advocacy group Public Citizen petitioned the Food and Drug Administration (FDA) on Apr. 10, 2006 to immediately remove the diet drug orlistat (XENICAL) from the market. The basis for the petition is the fact that orlistat can cause pre-cancerous changes in the lining of the intestines called aberrant crypt foci (ACF).
Orlistat was approved by the FDA in April 1999 for weight loss and weight maintenance when used in conjunction with a reduced-calorie diet. It is marketed by Roche Laboratories, Inc. of Nutley, NJ. Like other diet drugs, orlistat was approved by the FDA without scientific evidence showing that there is a health benefit for those who use the drug. In other words, there is no evidence that orlistat, or any diet drug, will reduce risk of premature death or illness associated with long-term obesity and inactivity.
According to the Petition:
Orlistat works in a different way than other diet drugs. It prevents enzymes in the gastrointestinal (GI) tract from breaking down dietary fats into smaller molecules that can be absorbed by the body. Thus, absorption of fat is decreased by about 30 percent, leading to the drug’s most common adverse effects: oily spotting, gas with discharge, fecal urgency, fatty/oily stools, and frequent bowel movements. Because orlistat reduces the absorption of some fat-soluble vitamins, patients must take a supplement that contains these vitamins (A, D, E, and K) and beta-carotene.
Public Citizen advises that you should not take orlistat as there is no evidence that this drug can reduce the health risks associated with obesity and inactivity, and the drug’s minimal effectiveness for weight loss-coupled with both the real and theoretical risks of orlistat-outweigh any know benefit for the drug.
Two research pathologists from the Case Western Reserve School of Medicine in Cleveland, OH joined Public Citizen in the petition. Their research, consisting of some 42 scientific papers on colorectal cancer, including 15 specifically on ACF, has helped to establish the relationship between ACF and colon cancer.