Weight gain: Side effect of atypical neuroleptics?

During clinical experience with the "atypical" neuroleptic drugs clozapine, risperidone, and zotepine, some patients have shown a marked weight gain, To prove whether weight gain is a relevant side effect of atypical neurolep tics, the charts of all patients admitted with DSM-LII-R diagnoses of schiz ophrenia, schizoaffective disorder, or delusional disorder in the years 199 1 to 1995 were evaluated. A retrospective chart review was performed, which included all patients who were treated longer than 2 weeks with a single n euroleptic. The data analysis showed that weight gain must be considered as a common side effect of atypical neuroleptics (clozapine, risperidone, sul piride, or zotepine). The mean weight gain (3.1, 1.5, 1.9, or 4.3 kg, respe ctively) was significantly higher than that of patients treated with "class ic" neuroleptics (mean, 0.0-0.5 kg) (Kruskal-Wallis, p = 0.01). Young and n ot obese patients show the highest weight increase. Because weight gain occ urs in the first weeks of treatment, particularly in previously untreated s ubjects, this side effect has to be considered in view of compliance with l ong-term neuroleptic medication.