ORLISTAT IS A LIPASE INHIBITOR FOR OBESITY MANAGEMENT THAT ACTS BY INHIBITING THE ABSORPTION OF DIETARY FATS. IT EXERTS ITS THERAPEUTIC ACTIVITY IN THE LUMEN OF THE STOMACH AND SMALL INTESTINE BY FORMING A COVALENT BOND WITH THE ACTIVE SERINE RESIDUE SITE OF GASTRIC AND PANCREATIC LIPASES. THE INACTIVATED ENZYMES ARE THUS UNAVAILABLE TO HYDROLYZE DIETARY FAT IN THE FORM OF TRIGLYCERIDES INTO ABSORBABLE FREE FATTY ACIDS AND MONOGLYCERIDES. AS UNDIGESTED TRIGLYCERIDES ARE NOT ABSORBED, THE RESULTING CALORIC DEFICIT MAY HAVE A POSITIVE EFFECT ON WEIGHT CONTROL. SYSTEMIC ABSORPTION OF THE DRUG IS THEREFORE NOT NEEDED FOR ACTIVITY. AT THE RECOMMENDED THERAPEUTIC DOSE OF 120 MG THREE TIMES A DAY, ORLISTAT INHIBITS DIETARY FAT ABSORPTION BY APPROXIMATELY 30%.