Buspirone/prolactin response in post head injury depression.

Fifty-five male patients who had suffered a mild head injury 11-13 months previously were investigated for evidence of depression. Eleven were diagnosed as DSM-III major depressives, nine with melancholia. Prolactin response to buspirone was examined in these patients, in eight male head-injured patients without depression and 10 age-matched male healthy controls. The prolactin response was significantly blunted in post head injury depressed patients compared to head injury non-depressed and healthy control groups. We suggest that these differences may be due to altered serotonin functioning post head injury.