Norpace

Norpace is the brand name for disopyramide, an antiarrhythmic medication in the class IA category. It works by blocking fast sodium channels in cardiac tissue and also has some potassium channel blocking effects, which together prolong the cardiac action potential and the refractory period. This action helps stabilize abnormal electrical activity in certain heart rhythms.

Norpace is used to treat a range of arrhythmias in adults, including ventricular tachycardia and certain supraventricular tachycardias. Because of its anticholinergic effects and potential to depress heart function, it is not always a first-line option and is typically considered when other therapies are unsuitable or ineffective. The drug is available in immediate-release form as Norpace and an extended-release form as Norpace CR, and it can be given orally or by injection in a hospital setting.

Contraindications to Norpace include known hypersensitivity to disopyramide, significant left ventricular dysfunction or heart failure, and other conduction abnormalities without appropriate pacing support. Caution is advised in the elderly and in patients with glaucoma, urinary retention, prostatic hyperplasia, electrolyte disturbances, or concurrent use of other drugs that prolong the QT interval. Disopyramide can cause dry mouth, blurred vision, urinary retention, and constipation due to its anticholinergic effects, as well as dizziness, hypotension, and the risk of proarrhythmia such as torsades de pointes, particularly in susceptible individuals.

Norpace should be used under close medical supervision with appropriate monitoring of heart rhythm and electrolytes.