Weight gain and sexual dysfunction are serious side effects of certain
antipsychotic drugs.
Ziprasidone, a novel
antipsychotic with a unique receptor binding profile, is reported to have a low propensity for such side effects. Previous results from this laboratory have demonstrated substantial
weight gain following sub-chronic treatment with
olanzapine and
risperidone.
Risperidone induced
weight gain and markedly impaired reproductive function while
olanzapine induced
weight gain, without affecting reproductive function. The aim of this study was to investigate effects of
ziprasidone on
weight gain and reproductive function in female rats.
Ziprasidone (1 and 2.5 mg/kg i.p.) or vehicle was administered once daily for 28 days and
body weight, food and water intake measured, in addition to histological examination of vaginal lavage to determine the stage of the oestrous cycle. On day 28, the rats were sacrificed and the uterine weights recorded, intra-abdominal fat weight and plasma
prolactin levels measured.
Ziprasidone failed to induce significant
weight gain during weeks 1-3, however, significant
weight gain was observed on day 28 at 2.5 mg/kg (p < 0.05).
Ziprasidone had no effect on food intake at any time point. A significant reduction in water intake (p < 0.05) was observed during the first week of treatment with 2.5 mg/kg
ziprasidone.
Ziprasidone had no effect on intra-abdominal fat weight, wet or dry uterine weight or plasma
prolactin levels. All
ziprasidone treated animals displayed a normal four-day oestrous cycle. This study is the first to report that
ziprasidone is without effect on reproductive function or ingestive behaviour in the rat.