The psychiatric side-effects of rimonabant.
OBJECTIVE
Experimental evidence has suggested that drugs that enhance cannabinoid type-1 (CB1) receptor activity may induce anxiolytic and antidepressant effects, whilst the opposite has been reported with antagonists. Thus, the objective of the present review is to discuss the potential psychiatric side-effects of CB1 receptor antagonists, such as rimonabant, which has been recently marketed in several countries for the treatment of smoking cessation, obesity and associated metabolic disorders.


METHODS
Literature searches were performed in PubMed and SciELO databases up to February 2009. The terms searched were 'obesity', 'rimonabant', 'cannabinoids', 'unwanted effects', 'diabetes', 'smoking cessation' and 'side-effects'.


RESULTS
Clinical trials have revealed that rimonabant may promote weight loss in obese patients, although it may also induce symptoms of anxiety and depression.


CONCLUSIONS
Patients taking CB1 receptor antagonists should be carefully investigated for psychiatric side-effects. These drugs should not be prescribed for those already suffering from mental disorders. Nevertheless, the development of new compounds targeting the endocannabinoid system for the treatment of several conditions would be necessary and opportune.
Moreira
Fabrício A
FA
Department of Pharmacology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
Crippa
José Alexandre S
JA
D001008:Anxiety Disorders / Q000139:chemically induced*; D001067:Appetite Depressants / Q000009:adverse effects*; D063385:Cannabinoid Receptor Modulators / Q000502:physiology; D003866:Depressive Disorder / Q000139:chemically induced*; D006801:Humans; D008659:Metabolic Diseases / Q000188:drug therapy; D009765:Obesity / Q000188:drug therapy*; D010880:Piperidines / Q000009:adverse effects*; D015990:Placebo Effect; D011720:Pyrazoles / Q000009:adverse effects*; D016032:Randomized Controlled Trials as Topic; D043884:Receptor, Cannabinoid, CB1 / Q000037:antagonists & inhibitors / Q000502:physiology; D000077285:Rimonabant; D012907:Smoking / Q000188:drug therapy*; D016540:Smoking Cessation / Q000379:methods
D001067:Appetite Depressants; D063385:Cannabinoid Receptor Modulators; D010880:Piperidines; D011720:Pyrazoles; D043884:Receptor, Cannabinoid, CB1; D000077285:Rimonabant