In vivo studies demonstrated isocarboxazid-driven inhibition of MAO in the brain, heart, and liver. The reduced MAO activity, caused by isocarboxazid, results in an increased concentration of serotonin, epinephrine, norepinephrine, and dopamine in storage sites throughout the central nervous system (CNS) and sympathetic nervous system. The increase of one or more monoamines is the basis for the antidepressant activity of MAO inhibitors like isocarboxazid.[1]

In vitro studies demonstrated isocarboxazid-driven inhibition of MAO in the brain, heart, and liver. The reduced MAO activity, caused by isocarboxazid, results in an increased concentration of serotonin, epinephrine, norepinephrine, and dopamine in storage sites throughout the central nervous system (CNS) and sympathetic nervous system. The increase of one or more monoamines is the basis for the antidepressant activity of MAO inhibitors like isocarboxazid.[1]