A trial has been performed investigating changes in weight in 99 female patients who have been treated with clopenthixol decanoate or perpehnazine enanthate after prior treatment with different oral neuroleptics. We found a significantly higher mean weight after the oral treatment period and a slight, but not statistically significant, further weight increase after the following depot period. In addition the rate of increase in weight was significantly lower during the depot treatment period. These increases might be due to achievement of a steady-state in weight during the first treatment period with oral intake. We found no difference between clopenthixol decanoate and perphenazine enanthate as regards change in weight or rate of change in weight.