Alli, the over-the-counter formula of the weight-loss drug orlistat, has not been taken off the market, as of 2015. Alli has been available for purchase in the United States since June 2007. Alli is also sold in the United Kingdom.
Alli, marketed by GlaxoSmithKline, contains 60 milligrams of orlistat, half of the amount in the prescription formula of the drug, which the drug company Roche markets as Xenical.
Orlistat, when paired with a reduced-calorie diet, promotes weight loss by inhibiting fat absorption in the intestines, further reducing overall caloric intake. Orlistat interacts with a number of other medications and should be taken under the direction of a doctor. Common side effects of orlistat include diarrhea, nausea and vomiting.