Alli (orlistat) Weight Loss Drug Available OTC

Medical Author: Melissa Conrad Stoppler, MD
Medical Editor: William C. Shiel, Jr., MD, FACP, FACR

The U.S. Food and Drug Administration approved orlistat capsules, branded as alli, as an over-the-counter (OTC) treatment for overweight adults in February, 2007. The drug had previously been approved in 1999 as a prescription weight loss aid, whose brand name is Xenical). The OTC preparation will have a lower dosage than prescription Xenical and is produced and sold by GlaxoSmithKline under the name of Alli.

Unlike appetite suppressants, orlistat (Xenical) works as a weight loss aid by acting upon the function of the gastrointestinal tract. The drug binds to an enzyme known as gastrointestinal lipase and inhibits the action of this enzyme, which plays a role in breaking down fats for absorption in the GI tract. As a result, up to 30% of ingested fat is not absorbed by the body.

Orlistat is recommended only for people 18 years of age and over in combination with a diet and exercise regimen. People who have difficulties with the absorption of food or who are not overweight should not take orlistat. Overweight is defined by the U.S. National Institutes of Health as having a body mass index (BMI) of 27 or greater.