Constipation is a common and potentially fatal side effect of clozapine treatment. Another important side effect of clozapine may also be significant weight gain. Orlistat is a weight-control medication that is known to induce loose stools as a common side effect. This study aimed to explore whether orlistat used to control clozapine-induced weight gain can simultaneously tackle clozapine-related constipation. In this 16-week randomized-controlled study, clozapine-treated patients received add-on orlistat (n=30) or add-on placebo (n=24). Colonic function was measured using the Bristol Stool Form Scale. There was a significant (P=0.039) difference in the prevalence of constipation in favor of orlistat over placebo in completers (n=40) at the endpoint. A decrease in the prevalence of constipation within the orlistat group (P=0.035) was observed (vs. no statistically significant changes in the placebo group). In clozapine-treated patients, orlistat may be beneficial not only for weight control but also as a laxative. As no established treatments for clozapine-induced constipation exist, orlistat can be considered for this population, although more studies are required.
aDepartment of Psychiatry, Helsinki University Central Hospital, Helsinki
bDepartment of Psychiatry, Vanha Vaasa Hospital, Vaasa
cDepartment of Psychiatry, Oulu University Hospital, Oulu
eThe National Institute for Health and Welfare
fDepartment of Psychiatry, University of Oulu, Oulu, Finland
Trial Registration: International Standard Randomized Controlled Trial Number, Register identifier ISRCTN65731856 (http://www.controlled-trials.com/isrctn).
Correspondence to Evgeny Chukhin, MD, Department of Psychiatry, Helsinki University Central Hospital, 00260 Helsinki, Finland Tel: +358 41 5058240; fax: +358 9 47163815; e-mail: firstname.lastname@example.org
Received July 21, 2012
Accepted October 4, 2012