Drug reference

Disopyramide

Antiarrhythmic

AntiarrhythmicATC C01BA03

CDSCO approvedATC C01BA03

EXCRETION

—

not curated

INTERACTIONS

12 major

incl. contraindicated

PREGNANCY

—

not curated

Top interactionssee all 12 →

AmisulprideContraindicatedDatabaseDDInter
AbarelixSevereDatabaseDDInter
AbirateroneSevereDatabaseDDInter
AcebutololSevereDatabaseDDInter

Mechanism

Disopyramide is an antiarrhythmic drug that exhibits an antimuscarinic effect. Its electrophysiological actions can lead to early afterdepolarization (EAD)-related triggered activity. This mechanism is associated with the potential to cause polymorphic ventricular tachycardia with QT interval prolongation.

Indications

Control of arrhythmias after myocardial infarction (including those not responding to lidocaine hydrochloride)Supraventricular arrhythmiasVentricular arrhythmiasMaintaining sinus rhythm in atrial flutterMaintaining sinus rhythm in atrial fibrillationPrevent recurrence of ventricular tachycardiaPrevent recurrence of ventricular fibrillationHypertrophic cardiomyopathy (to decrease dynamic outflow tract obstruction)Prevention of recurrences of ventricular arrhythmia (second line drug)Maintenance therapy after cardioversion of atrial fibrillation (AF)Maintenance therapy after cardioversion of atrial flutter (AFl)

Dosing

Adult: Can be given by intravenous injection to control arrhythmias after myocardial infarction. Oral administration is also useful.
Renal adjustment: Dose should be reduced in patients with renal dysfunction.

Pharmacokinetics

Half-life

4–10 h

Bioavailability

Well absorbed

Protein binding

Concentration dependent

Metabolism

Hepatic (to a weakly active metabolite)

Excretion

nearly half excreted unchanged in urine

Contraindications

Patients susceptible to angle-closure glaucoma
Patients with prostatic hyperplasia
Heart failure
Prostatism
Glaucoma
Prolonged QT interval

Side effects

Common

Antimuscarinic effectImpaired cardiac contractilityDry mouthUrinary retentionConstipationPrecipitation of glaucomaUrinary retention (especially in elderly males)Blurred vision

Serious

Polymorphic ventricular tachycardia with prolonged QT interval (torsades de pointes)
Torsades de pointes
Depression of contractility (can precipitate heart failure)
Depression of cardiac contractility
Cardiac decompensation (in patients with damaged hearts)
Hypotension (in patients with damaged hearts)