Date - 17 August 2004

Source - Drugs in Context 2004; 1D(6): Orlistat - Obesity p205

Author - Dr Eleanor Bull

The anti-obesity agent orlistat is a potent and selective inhibitor of gastrointestinal lipases which promotes weight loss by inhibiting the hydrolysis and absorption of ingested fat. When administered at the recommended dosage, orlistat can block up to 30% of ingested fat calories, without disrupting the normal physiological functioning of the digestive system. Orlistat is indicated in obese adult patients with a body mass index (BMI) of equal to or greater than 30 kg/m2 or equal to or greater than 28 kg/m2 with concomitant risk factors (e.g. type 2 diabetes, hypertension and hypercholesterolaemia). Patients should also be encouraged to adopt changes to their diet and lifestyle in conjunction with orlistat in order to maximise treatment success. Orlistat is effective and well tolerated in patients with type 2 diabetes, hypertension or hypercholesterolaemia and may even slow concomitant disease progression in some cases, probably as a consequence of weight reduction. It has also been shown to delay the onset of type 2 diabetes in obese impaired glucose tolerance patients in a 4-year trial. The adverse event profile of orlistat is generally mild-to-moderate in intensity, although the incidence of gastrointestinal side-effects is usually elevated in the initial stages of treatment as the patient learns which foods are high in fat. This may impede patient concordance unless the correct support and advice is received.

Keywords: Orlistat, Obesity