Within the drug safety program in psychiatry AMSP ( Arzneimittelsicherheit in der Psychiatrie), severe adverse drug reactions (ADRs) are assessed. Currently 35 psychiatric hospitals and departments are participating in detecting severe ADRs. This paper focuses on prolactin-dependent ADRs such as gynecomastia and galactorrhea due to psychotropic medications. Related to the number of patients surveyed (122,562 from 1993 to 2000), these are rare events (0.03 % or 35 cases). Imputed drugs were mostly antipsychotics, but antidepressants were also imputed in single cases. In the group of antipsychotics, relative frequencies of galactorrhea were highest for amisulpride and risperidone and corresponded to the degree of D2 binding. Galactorrhea assessed as "severe" was accompanied by distressing symptoms such as pain, tension, enlargement of breasts, or soaked clothing. The AMSP data contribute to the knowledge on endocrine ADRs by the large number of patients examined and help clinicians select the appropriate drug if their patients have been prone to for these ADRs in the past.