Basal prolactin values correlate with response to reboxetine treatment in major depression, but not with response to citalopram.

Little is known about variables that might predict outcome in major depression. Recently, basal prolactin values (BPV) have been suggested to predict response to treatment with tricyclic antidepressive drugs. In order to examine whether BPV predict response to selective mono-aminergic therapy, 24 in-patients with major depression were treated in a single-masked, randomised study using the most selective noradrenergic or serotonergic reuptake inhibitors available for antidepressant treatment, i.e. reboxetine and citalopram. A significant correlation between BPV and treatment response to reboxetine was found, but not between BPV and response to citalopram. As BPV are influenced by noradrenergic activity, it can be hypothesized that depressed patients with comparatively high BPV have a relatively high noradrenergic function. This might explain why in our study depressed patients with the highest BPV responded strongest to selective noradrenergic treatment with reboxetine. As measurement of BPV is simple, further studies are suggested to examine the possible clinical value of the link between prolactin, noradrenergic function in major depression and treatment response.