Urinary amine metabolites in depression: a combined biochemical and general practice study: II. Biochemical aspects.

Peripheral measures of amine metabolites may be related to response to treatment with antidepressants. Urinary studies of MHPG levels have indicated a different response to treatment between patients with low levels who responded well to imipramine and those who responded well to amitriptyline. Such findings lead to the consideration of the newer antidepressants such as clomipramine and maprotiline, with their more selective actions on the individual amine systems, as the medication of choice for specific groups of patients. It was hypothesized that patients having a low excretion of MHPG might have deranged noradrenaline metabolism, and therefore respond best to maprotiline and conversely a low excretion of 5 HIAA might indicate a derangement of serotonin metabolism and therefore a good response to clomipramine. A clinical study, however, showed that changes in amine levels, interesting though they were with respect to the response to medication, were not consistent with the known preferences of maprotiline and clomipramine for single amine systems. There was no evidence of the existence of clearly defined groups within the population studied having a derangement of a single amine system.