OBJECTIVE: The purpose of this study was to estimate and compare the effects of 
antipsychotics-both the newer ones and the conventional ones-on body weight.
METHOD: A comprehensive literature search identified 81 English- and 
non-English-language articles that included data on weight change in 
antipsychotic-treated patients. For each agent, a meta-analysis and random 
effects metaregression estimated the weight change after 10 weeks of treatment 
at a standard dose. A comprehensive narrative review was also conducted on all 
articles that did not yield quantitative information but did yield important 
qualitative information.
RESULTS: Placebo was associated with a mean weight reduction of 0.74 kg. Among 
conventional agents, mean weight change ranged from a reduction of 0.39 kg with 
molindone to an increase of 3.19 kg with thioridazine. Among newer antipsychotic 
agents, mean increases were as follows: clozapine, 4.45 kg; olanzapine, 4.15 kg; 
sertindole, 2.92 kg; risperidone, 2.10 kg; and ziprasidone, 0.04 kg. 
Insufficient data were available to evaluate quetiapine at 10 weeks.
CONCLUSIONS: Both conventional and newer antipsychotics are associated with 
weight gain. Among the newer agents, clozapine appears to have the greatest 
potential to induce weight gain, and ziprasidone the least. The differences 
among newer agents may affect compliance with medication and health risk.