Comparative evaluation of fecal fat excretion induced by orlistat and chitosan

To compare the effects of chitosan and orlistat on fecal fat excretion.

A randomized, open-label, two-period sequential design study was used. A total of 12 healthy adult volunteers within 20% of their ideal body weight entered a 7-day run-in diet period before being randomized to orlistat (120 mg) or chitosan (890 mg) three times daily for 7 days. Subjects then crossed over treatment regimens for an additional 7-day period. Subjects followed a standardized diet (2500 kcal/d, 30% as fat) for the entire 21-day study. Feces were collected on days 4 to 7 of the run-in period (baseline) and during the two treatment periods. Mean daily fecal fat excretion was measured at baseline and during each treatment regimen.

Mean baseline fecal fat excretion for all subjects was 1.36 +/- 0.45 g/d. During orlistat treatment, mean fecal fat excretion significantly increased from baseline (+16.13 +/- 7.27 g/d; p < 0.001). No significant effect was observed with chitosan (+0.27 +/- 1.02 g/d; p = 0.379). Fecal fat excretion was significantly greater with orlistat than with chitosan (p < 0.001; 95% confidence intervals: 11.73; 20.00 g/d).

This study provides additional evidence of the inhibitory effect of orlistat on dietary fat absorption. Chitosan, however, has no effect on fecal fat excretion.