BOTH SEROTONIN and norepinephrine are amines in the central nervous system which have been implicated in the production of psychiatric symptomatology. Behavioral changes were reported in schizophrenic patients who were given the serotonin precursor, tryptophan, with a monoamine oxidase inhibitor (MAOI).1-4 However, some of these studies also involved the use of methionine.3-5 Tryptophan has been shown to potentiate the antidepressant effects of MAOI in affective states.6,7 In contrast to these indole studies, the role of norepinephrine in affective states has been recently reviewed by Schildkraut,8 but there are as yet few supportive clinical studies.9-12
Although some of the above studies were of longitudinal type, they were not conducted on patients with periodic illness. Furthermore, the interpretations of the importance of the drug actions were in terms of either serotonin or norepinephrine but not the combination. In this communication we