Growth hormone (GH) responses to growth hormone releasing hormone (GHRH) of 53 in-patients meeting DSM-III-R criteria for major depressive episode with melancholia (24 non-delusional and 23 delusional depression) were compared with those of 19 healthy controls. No significant differences in basal GH were found between the control and either the non-delusional or the delusional groups. The whole group of depressed patients showed a significantly lower response than the control patients at all points of the GH response to GHRH curve as well as a lower area under curve. When the three groups (control, delusional and non-delusional depressed) were compared, it was found that only the non-delusional depressed patients had a significantly lower area under curve and lower values at +60, +90 and +120 min than the controls. The only significant difference between the two groups of depressed patients was that the delusional group showed a delayed appearance of the maximum response peak and a more prolonged response.