The Effect of Orlistat, an Inhibitor of Dietary Fat Absorption, on the Pharmacokinetics of β‐Carotene in Healthy Volunteers

Abstract

To assess the influence of orlistat, a lipase inhibitor, on the absorption of β‐carotene, an open‐label, parallel, placebo‐controlled, randomized, two‐way crossover study was performed in 48 healthy volunteers between the ages of 19 and 58 years. Each subject received a single oral dose of 0, 30, 60, or 120 mg β‐carotene (12 subjects per dose level) on the fourth day of treatment with orlistat (120 mg) or placebo 3 times a day for 6 days. The treatments were separated by a washout period of at least 5 weeks. Serial blood samples were collected before and at appropriate intervals after administration of β‐carotene to determine plasma concentrations of unchanged β‐carotene. Short‐term (3 to 6 days) treatment with orlistat did not alter endogenous profiles of β‐carotene in plasma. When β‐carotene was given during orlistat treatment, its absorption was reduced by approximately one‐third. This reduction was consistent for all three dose levels of β‐carotene studied; however, the results for the 30‐mg dose level were subject to greater variability, particularly for area under the concentration—time curve (AUC). It was concluded that two thirds of a supplemental dose of β‐carotene will be absorbed during orlistat treatment; this may be sufficient to achieve physiologic levels of β‐carotene with an appropriate dose of β‐carotene, should supplementation be needed in obese patients who have developed β‐carotene deficiency during therapy with orlistat.