[The influence of lithium salts and antidepressive medication on the serum prolactin level (author's transl)].

The prolactin (hPRL) level in the serum of 17 patients (10 females, 7 males) with primary depression (manic-depressive disease) was determined before and after prophylactic treatment with lithium salts. All patients were free of acute psychotic-depressive symptomes. However, 9 of 17 patients received moderate doses of additional antidepressive medication continuously for 4 weeks. No significant changes of the serum hPRL were observed in the group as a whole, the lithium serum levels being within the normal therapeutic range. The mean hPRL level in patients with concomitant antidepressive medication was significantly higher as compared to the "only lithium" group, but never exceeded the normal range in both groups. Considering similar results of other authors, it is suggested that lithium does not influence the hPRL serum level, at least if no special methods of hPRL stimulation are used. However, with regard to recent communications suggesting that besides dopaminergic influences also serotonergic mechanisms play an important part in hPRL regulation, it is held that the prolactin response in lithium-treated patients warrants further investigations using serotonergic stimulation methods.