["To examine and record the clinical antidepressant effect of exogenous agmatine, an amino acid derived central glutamaergic modulator in endogenously depressed subjects. It was also the author's intention to examine the effects of parachlorophenylalanine (PCPA) in therapeutic responders to determine if serotonergic mechanisms mediate agmatine's antidepressant effect. Methodology Exogenous agmatine was ingested in doses of 2-3mg/day by depressed subjects with Major Depresssive Disorder (MDD), clinically assessed using the 21 item Hamilton Rating Scale for Depression (HAM-D), the Clinical Global Impression (CGI) and the Brief Psychiatric Rating Scale (BPRS). Antidepressant responders volunteered to concommittantly ingest parachlorophenylalanine (PCPA) at starting doses of 250mg/day, and increased until depressive relapse, mitigating side effects, or a maximum dosage of 1250mg/day.", 'Three depressed subjects showing total illness remission with exogenous agmatine did not relapse after concomitantly adding PCPA. Effective in relieving both psychomotor agitation and retardation, the antidepressant effect was free of physical or behavioural side effects: gastrointestinal discomfort and loose stools in one subject resolved spontaneously within days. All three subjects refused to risk depressive relapse by temporarily stopping agmatine after PCPA was stopped.'] Is the clinical antidepressant effect of exogenous agmatine reversed by parachlorophenylalanine : a pilot study?