The government on Wednesday approved over-the-counter sales of the fat-blocking diet pill orlistat, allowing direct sales for the first time of a version of a diet drug that had been available only by prescription.
Currently available as Xenical, the capsules will be sold in a lower, nonprescription dose under the name "alli."
The drug is intended for people 18 and older to use along with a reduced-calorie, low-fat diet and exercise.
When taken with meals, orlistat blocks the absorption of about one-quarter of any fat consumed. That fat — about 150 to 200 calories worth — is passed out of the body in stools, which can be loose as a result. About half of patients in trials experienced gastrointestinal side effects.
The new drug would contain half the dose of Xenical prescription capsules and would cost consumers $12 to $25 a week, GlaxoSmithKline has said. The company estimated 5 million to 6 million Americans a year would buy the drug over the counter. Those numbers could mean at least $1.5 billion a year in retail sales.
The Food and Drug Administration said the most common side effect of the product is a change in bowel habits. Eating a low fat diet will reduce the likelihood of this side effect.
Also, FDA said people who have had organ transplants should not take OTC orlistat because of possible drug interactions. In addition, anyone taking blood thinning medicines or being treated for diabetes or thyroid disease should consult a physician before using orlistat, the agency said.
GSK Consumer Healthcare, which will market the pill, said it chose the name alli to indicate a partnership with consumers in their weight-loss efforts.
"We know that being overweight has many adverse consequences, including an increase in the risk of heart disease and type 2 diabetes," said Dr. Douglas Throckmorton, deputy director for the FDA's Center for Drug Evaluation and Research.
"OTC orlistat, along with diet and exercise, may aid overweight adults who seek to lose excess weight to improve their health," he said.