Serum prolactin level increase in normal subjects following administration of perphenazine oral dosage forms:...

Two pilot studies were performed to determine if oral phenothiazine products could generate a significant increase in serum levels of the hormone prolactin. The two studies employed three and four healthy normal male subjects, respectively. In the first study the subjects received a screening dose, a placebo, one 8-mg perphenazine tablet, and two 8-mg perphenazine tablets. In the second study, the subjects were dosed with two 10-mg amitriptyline tablets, one 10-mg amitriptyline tablet with one combination tablet containing 10 mg of amitriptyline and 4 mg of perphenazine, and two combination tablets, each containing 10 mg of amitriptyline and 4 mg of perphenazine. In both cases the drug treatments produced a significant rise in the serum prolactin levels versus a placebo or control. This increase was defined as a prolactin response. The possible utility of this response in bioavailability testing is discussed.