An occasional side effect is a rapid or irregular heartbeat. Alcohol may exacerbate some of its side effects. Overdose
The symptoms and the treatment of an overdose are generally the same as for the other TCAs, including anticholinergic effects,  serotonin syndrome and adverse cardiac effects. TCAs, particularly nortriptyline, have a relatively narrow therapeutic index, which increase the chance of an overdose (both accidental and intentional). Symptoms of overdose include: irregular heartbeat, seizures, coma, confusion, hallucination, widened pupils, drowsiness, agitation, fever, low body temperature, stiff muscles and vomiting. Interactions
Excessive consumption of alcohol in combination with nortriptyline therapy may have a potentiating effect, which may lead to the danger of increased suicidal attempts or overdosage, especially in patients with histories of emotional disturbances or suicidal ideation. It may interact with the following drugs:
heart rhythm medications such as flecainide (Tambocor), propafenone (Rhythmol), or quinidine (Cardioquin, Quinidex, Quinaglute)
cimetidine
guanethidine
reserpine

Pharmacology
Nortriptyline is a strong norepinephrine reuptake inhibitor and a moderate  serotonin reuptake inhibitor. Its pharmacologic profile is as the table shows with (inhibition or antagonism of all sites). Pharmacodynamics
Nortriptyline is an active metabolite of amitriptyline by demethylation in the liver. Chemically, it is a secondary amine dibenzocycloheptene and pharmacologically it is classed as a first-generation antidepressant.Nortriptyline may also have a sleep-improving effect due to antagonism of the H1 and 5-HT2A receptors. In the short term, however, nortriptyline may disturb sleep due to its activating effect.
Localized granuloma annulare is a skin condition of unknown cause, tending to affect children and young to middle-aged adults, usually appearing on the lateral or dorsal surfaces of the fingers or hands, elbows, dorsal feet, and ankles. : 703

See also
Granuloma annulare
Skin lesion


== References ==