NCIt definition : A dibenzoxepin derivative and tricyclic antidepressant (TCA) with antipruritic, antidepressive
and anxiolytic activities. Doxepin blocks the reuptake of norepinephrine and serotonin
(5-HT) into presynaptic terminals thereby prolonging the availability of the monoaminergic
neurotransmitters within the synaptic cleft and enhancing their neurotransmission.
Doxepin also has antagonistic effects on histamine H1, 5-HT2, alpha-1 adrenergic,
and muscarinic receptors. The antipruritic effect of this agent is mediated through
inhibition of histamine receptors.;