Imipraminoxide (Imiprex, Elepsin), or imipramine N-oxide, is a tricyclic antidepressant (TCA) that was introduced in Europe in the 1960s for the treatment of depression.[1][2][3][4]

Imipraminoxide is both an analogue and a metabolite of imipramine, and has similar effects.[5][6][7][8] However, in clinical trials, imipraminoxide was found to have a faster onset of action, slightly higher efficacy, and fewer and less marked side effects, including diminished orthostatic hypotension and anticholinergic effects like dry mouth, sweating, dizziness, and fatigue.[5][6][7][8][9][10]

Imipraminoxide's pharmacology has not been well elucidated, but based on its very close relationship with imipramine, it likely acts as a serotonin and norepinephrine reuptake inhibitor and serotonin, adrenenaline, histamine, and muscarinic acetylcholine receptor antagonist, though with weaker antiadrenergic and anticholinergic actions.[9][10]

See also