The efficacy of Orlistat is to control body weight, etc., the role is to treat obesity, etc., the usage is to take the drug with or after meals, etc., patients should follow the doctor’s instructions. Orlistat commonly used dosage form for capsules, can inhibit gastrointestinal lipase, so that the enzyme inactivation, can not hydrolyze the fat in the food, so that the fat can not be absorbed by the body, reduce calorie intake, so as to control body weight. It is used to treat obesity and overweight. Orlistat is taken as 1 capsule by mouth within 1 hour after or with a meal. One dose of the medication may be discontinued if there is an uneaten meal or if the food does not contain fat. Adverse reactions to Orlistat are increased gastrointestinal emissions, increased frequency of stools, oily stools, urgency of stools, steatorrhea, and fecal incontinence. The drug is contraindicated in pregnant women, those who are allergic to the product, cholestasis, chronic malabsorption syndrome, organic obesity. Patients should use the drug under medical supervision.