非典型抗精神病劑（Atypical antipsychotics），比起傳統抗精神病劑，大幅地減少了錐體外徑方面的副作用。隨著使用廣泛，一些副作用陸續被報導，體重增加（weight gain）即是其中一項。
本文以某精神專科醫院住院病患為研究對象，採電腦篩選、回顧性的方式進行藥物使用評估（drug use review），探討服用五種非典型抗精神病劑，包括clozapine、olanzapine、risperidone、quetiapine、zotepine，各組藥物對體重及體質指數BMI的影響。共納入133位病患，為期12週之研究結果發現，以單一藥物組來看，olanzapine組BMI增加達統計上差異（P ≤ 0.05），其他組BMI均無顯著差異。另外，精神病慢性住院病患平均BMI，普遍有過高的情形。
 

Atypical antipsychotics as compared to traditional antipsychotics can reduce the adverse effects of extrapyramidal symptoms considerably. Although this type of drugs is widely used, some adverse effects have been reported, one of which is weight gain. 
The research employed schizophrenic inpatients in an anonymous hospital in Taiwan as research objects, and computer sampling and retrospective drug use review to investigate how five kinds of atypical antipsychotics, including clozapine, olanzapine, risperidone, quetiapine and zotepine, influence weight and Body Mass Index (BMI). Total 133 patients were studied, and from the research, which lasted for 12 weeks, we found out that patients taking olanzapine showed statistically significant increase of BMI (P ≤ 0.05) where as no significant difference was observed in the studies of other drugs. Generally, chronic schizophrenic inpatients tend to have an excessively elevated BMI.