Sinequan
Doxepin is 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.