The effect of desipramine upon central adrenergic function in depressed patients.

Eleven drug free patients meeting Research Diagnostic Criteria for Major Depressive Disorder have been treated with desipramine and given a clonidine infusion after 0, 1 and 3 weeks of treatment. The sedative and hypotensive effects of clonidine were significantly inhibited after three weeks of treatment with desipramine: a similar interaction was seen after one week of treatment although this just failed to reach statistical significance. The growth hormone (GH) response to clonidine was initially impaired, but increased significantly after one week of treatment. A significant reduction in the GH response occurred during the second and third weeks of treatment with desipramine. This last finding is interpreted as evidence of adaptive change of alpha 2 adrenoceptors: the other changes can be explained by the known ability of desipramine to block the re-uptake of noradrenaline.