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Article Abstract

Early reports of the discovery of antidepressants in the 1950s have remained as little-known findings.Had the discovery of isoniazid, an agent with no clear action on monoamine systems, and that of reserpine,which depletes monoamines, been more widely known, then the monoamine lesion theories of depression,as proposed by Schildkraut in 1965, may not have been written. If the lesion in depression is lowered brainmonoamine levels, then antidepressant agents that increase monoamine levels should work for all patients.If this were the case, optimizing treatment effect sizes with a minimum of side effects and some demonstrablespecificity to depressive disorders would be possible. This is not the profile of antidepressants inclinical practice. Alternatively, if antidepressants act on constitutional types to provide appropriate therapeuticprinciples, then the efficacy would stem from an ability to suppress symptoms and to elicit or maintainconditions that allow recovery in a subgroup of patients who would otherwise remain nonresponsive.Current monoamine selective antidepressant principles embody “get-up-and-go” (noradrenergic) andemotional reactivity-reducing (serotonergic) principles. Different antidepressants are, therefore, likely tohave different treatment effect sizes in different constitutional types. A further important aspect of antidepressantselectivity will lie in the extent to which these agents promote a sense of well-being during themaintenance phase of treatment.