The Use of Sodium Bicarbonate in the Treatment of Tricyclic Antidepressant-Induced Arrhythmias

Sodium bicarbonate has been successfully used clinically to treat arrhythmias induced by tricyclic antidepressant drugs (imipramine, amitriptyline, nortriptyline, dibenzepin). Experiments conducted on puppies showed that arrhythmias caused by amitriptyline disappear when acidosis is adequately treated. Plasma protein binding of amitriptyline increases as pH rises, reducing the unbound fraction of drug. This mechanism is an important factor in the antiarrhythmic action of sodium bicarbonate in tricyclic antidepressant overdosage.