Orlistat is a lipid lowering agent. It is a first drug to treat obesity which does not act as an appetite suppresant. It binds to active site of GI lipase,enzyme which breakdowns triglycerides into its their component parts, and thus makes it unavailable for absorption. Thus site of action being gut, it does not get absorped into systemic circulation and hence wont produce much side effects other than fat and oily stools,increased and frequent defecation, fecal incontinence, gases, oily spotting. Some patients treated with orlistat have experienced discomfort, nausea, vomiting, constipation, cholelithiasis and abdominal and rectal pains. Tooth and gum problems were also recorded.