Abstract: The analgesic tramadol has many characteristics in common
with the antidepressant venlafaxine. The drugs are structurally
similar, share both serotonergic and noradrenergic properties, and
undergo a similar metabolic fate. In this study, a patient, who developed
significant depression following cessation of tramadol after
several years of therapy, is described. Her depression was then
treated with venlafaxine with excellent response. It appears that
tramadol may have provided a prophylactic antidepressant effect in
this patient. Because of its similarities to venlafaxine, tramadol may
possibly exert a degree of antidepressant effect in certain patients,
particularly those with chronic pain

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