Incorrect use and limited weight reduction of orlistat (Xenical) in clinical practice. A cohort study

To study the prescribing of the antiobesity drug orlistat in relation to the approved indication and its weight-reducing effect in clinical practice during the first 3 months of treatment.

Anonymous postal questionnaire survey to prescribers of orlistat concerning a random sample of 1000 of 20,000 prescriptions.

Useful information was obtained for 789 patients.

Primary and secondary care in Sweden.

Beginning and continued treatment according to the approved indication. Dropout from treatment. Weight loss during treatment.

Four percent of the patients were prescribed orlistat despite having a body mass index (BMI) less than 28 kg/m2. Only 24% of the patients had a diet period with a weight loss of 2.5 kg or greater before the start of therapy. Half of the patients with a weight loss of less than 5% after 3 months continued the treatment. Ten percent gained weight or had no weight loss at all while 43% lost less than 5% in weight. At least one-quarter of the patients stopped the treatment within the observation period.

Orlistat was not prescribed according to the approved indication in the majority of cases. The dropout rate was high and most patients had minor gain from the treatment.