Hazard and Precautionary Statements (GHS)

Disopyramide Chemical Properties,Usage,Production

Clinical Use

Ventricular and supraventricular arrhythmias

Drug interactions

Potentially hazardous interactions with other drugs
Anti-arrhythmics: increased myocardial depression with other anti-arrhythmics; amiodarone and dronedarone increase risk of ventricular arrhythmias - avoid.
Antibacterials: concentration possibly increased by azithromycin, clarithromycin and erythromycin (risk of toxicity); increased risk of ventricular arrhythmias with moxifloxacin - avoid; possibly increased risk of ventricular arrhythmias with telithromycin and delamanid; concentration reduced by rifamycins.
Antidepressants: increased risk of ventricular arrhythmias with tricyclics; increased risk of ventricular arrhythmias with citalopram and escitalopram - avoid.
Antifungals: increased risk of ventricular arrhythmias with ketoconazole - avoid; avoid with itraconazole.
Antihistamines: increased risk of ventricular arrhythmias with mizolastine.
Antihypertensives: increased myocardial depression and asystole with beta-blockers or verapamil; increased risk of ventricular arrhythmias with sotalol
Antimuscarinics: increased risk of antimuscarinic side effects; increased risk of ventricular arrhythmias with tolterodine.
Antivirals: concentration possibly increased by ritonavir, increased risk of toxicity; increased risk - avoid.

Metabolism

Disopyramide is partially metabolised in the liver by the cytochrome P450 isoenzyme CYP3A4. The major metabolite is mono-N-dealkylated disopyramide which retains some antiarrhythmic and antimuscarinic activity. The major route of excretion is through the kidney, about 50-60% as the unchanged drug, 20% as the N-dealkylated metabolite, and 10% as other metabolites. 64% of the N-dealkylated metabolite is excreted via the faeces.