Side effect and health status changes were measured in 3 studies in which outpatients experiencing suboptimal efficacy or tolerability with their current antipsychotic were switched to 6 weeks of open-label ziprasidone. The studies differed only in the patient's prior antipsychotic; 1 study group was on olanzapine (n = 104), a second on risperidone (n = 58), and third on a conventional antipsychotic (n = 108). Baseline and end point health status measures included weight and height, nonfasting cholesterol, and triglyceride levels, prolactin levels, and extrapyramidal side effects. Improvements in health indices and side effects were seen among all 3 groups, but the specific benefits depended on the preswitch antipsychotic. For example, patients switched from olanzapine experienced a mean weight loss of 1.76 kg (P < 0.0001), those switched from risperidone had a lesser reduction in weight (-0.86 kg; P = 0.015), and those switched from conventionals had a nonsignificant increase (+0.27 kg; P = 0.3). Prolactin levels decreased among those switched from risperidone (P < 0.0001) or conventionals (P = 0.05), but not for patients switched from olanzapine. EPS improved among those switched from conventionals (P < 0.0001) and to a lesser extent among those switched from risperidone (P < 0.01), but not in those changed from olanzapine (NS). Thus, in these studies, switching to ziprasidone in patients with continuing symptoms or side effects on their current medication was often associated with improved health status indices, lowered prolactin levels, or less EPS, with the magnitude benefit consistent with the known side-effect profile of the preswitch antipsychotic.
The atypical antipsychotic ziprasidone has demonstrated broad-spectrum efficacy in patients with acute exacerbation of schizophrenia and schizoaffective disorder and low incidences of clinically significant weight gain, prolactin elevation, extrapyramidal side effects (EPS), and postural hypotension. 1-5 What is not known, however, is whether these theoretical differences in side-effect profiles translate into actual clinical differences when patients change from one medication to another. For example, it is not known whether the weight neutrality of ziprasidone, as seen in long-term clinical trials, translates into weight loss when patients switch from other antipsychotics.
These studies examined changes in various common side effects seen with antipsychotics (EPS, prolactin, and weight), changes in common laboratory markers of health status, and other tolerability parameters after 6 weeks of ziprasidone therapy in stable outpatients with schizophrenia who were switched from their previous antipsychotic, a conventional antipsychotic, risperidone, or olanzapine. Data on changes in symptoms and global illness severity in these studies have been reported elsewhere. 6