<unk>  is a drug designed to treat obesity. It is marketed as a prescription drug under the trade name Xenical by Roche in most countries, and is sold over-the-counter as Alli by GlaxoSmithKline in the United Kingdom and the United States. Its primary function is preventing the absorption of fats from the human diet by acting as a lipase inhibitor, thereby reducing caloric intake. It is intended for use in conjunction with a healthcare provider-supervised reduced-calorie diet.<unk>  is the saturated derivative of lipstatin, a potent natural inhibitor of pancreatic lipases isolated from the bacterium Streptomyces toxytricini. However, due to its relative simplicity and stability,<unk>  was chosen over lipstatin for development as an anti-obesity drug. The effectiveness of<unk>  in promoting weight loss is definite but modest. Pooled data from clinical trials suggest that people given<unk>  in addition to lifestyle modifications, such as diet and exercise, lose about more than those not taking the drug over the course of a year.<unk>  also modestly reduces blood pressure and appears to prevent the onset of type 2 diabetes, whether from the weight loss itself or other effects. It reduces the incidence of diabetes type II in people who are obese around the same amount that lifestyle changes do. Benefits aside, however,<unk>  is noted for its gastrointestinal side effects (sometimes referred to as treatment effects), which can include steatorrhea (oily, loose stools). They decrease with time, however, and are the most frequently reported adverse effects of the drug. In Australia, the United States and the European Union,<unk>  is available for sale without a prescription. Over-the-counter approval was controversial in the United States, with consumer advocacy group Public Citizen repeatedly opposing it on safety and efficacy grounds. Generic formulations of<unk>  are available in some countries. In Australia it has been listed as an S3 medication—available from a pharmacist without a prescription—since 2000.
Orlistat
Ketotifen
Atorvastatin
Tolbutamide
Clofibrate
Cobicistat
Udenafil
Migalastat