The authors determined serum prolactin levels in 13 patients receiving
clozapine, an antipsychotic drug that does not produce extrapyramidal side
effects. Morning serum prolactin levels, 11 hours after the last dose, were
not elevated during chronic treatment with clozapine in any subject despite
its therapeutic effects. Serum prolactin levels were moderately increased
between 90 minutes and 4 hours after administration of very high doses of
oral clozapine in 4 patients but were smaller than those produced by
chlorpromazine in other subjects. The authors suggest that clozapine in
other subjects. The authors suggest that clozapine may achieve its
antipsychotic effect differently than do classical neuroleptics and that
sustained prolactin increases are not essential for antipsychotic
action.Abstract Teaser