NCIt definition : A tricyclic antidepressant agent used for short-term treatment of various forms of
depression. Nortriptyline blocks the norepinephrine presynaptic receptors, thereby
blocking the reuptake of this neurotransmitter and raising the concentration in the
synaptic cleft in the CNS. Nortriptyline also binds to alpha-adrenergic, histaminergic
and cholinergic receptors. Long-term treatment with nortriptyline produces a downregulation
of adrenergic receptors due to the increased stimulation of these receptors.;