Disopyramide

Registered South African indications:

• Unifocal and multifocal premature ventricular contractions
• Premature atrial contractions
• Paroxysmal atrial tachycardia

Contraindications

• Hypersensitivity to the active ingredient or any of its excipients
• Second or third degree atrioventricular block without pacemaker
• Bundle–branch block associated with first degree atrioventricular block 
• Unpaced bifasicular block
• Prolonged QT interval
• Severe sinus node dysfunction 
• Severe heart failure (except if secondary to cardiac arrhythmia)
• Coadministration with other antiarrhythmic agents
• Coadministration with other agents known to provoke ventricular arrhythmias

Cautions

• Pregnancy
• Breastfeeding
• Hepatic impairment
• Renal impairment
• Elderly
• Porphyria
• Asymptomatic ventricular premature contractions
• Structural heart disease
• Malnourished patients
• Diabetes mellitus
• Electrolyte imbalance
• Narrow–angle glaucoma
• Benign prostatic hyperplasia
• Myasthenia gravis
• May impair ability to drive and operate machinery

Forms avail. in SA and covered in this monograph: cap

Unifocal and multifocal premature ventricular contractions
Premature atrial contractions
Paroxysmal atrial tachycardia

Loading dose

• <50kg: Oral (cap): 200mg, as a single dose
• >50kg: Oral (cap): 300mg, as a single dose

Maintenance

• Oral (cap): 300-800mg/day, in 3-4 divided doses

Not established for use in children

Pregnancy

• Caution
• Although Disopyramide has undergone animal tests for teratogenicity without evidence of any effect on the developing foetus, its safety in human pregnancy has not been established. Disopyramide has been reported to stimulate contractions of the pregnant uterus. The agent should only be used in pregnancy if the benefits clearly outweigh the possible risks to the mother and foetus

Breastfeeding

• Caution; not recommended
• Studies have shown that oral disopyramide is secreted in breast milk although no adverse effects to the infant have been noted. However, clinical experience is limited and disopyramide should only be used during breastfeeding if, it is essential for the welfare of the patient. The infant should be closely supervised, particularly for anti-cholinergic effects and drug levels determined if necessary. Ideally, if the disopyramide is considered essential an alternative method of feeding should be used

Renal Impairment

• Caution; dose adjustment recommended
• No dose adjustment for loading dose 

Hepatic Impairment

• Caution; dose adjustment recommended
• No dose adjustment for loading dose

Elderly

• Caution; no dose adjustment recommended
  Initiate at the lower end of dosage range

Porphyria Information

• Probably porphyrinogenic (PRP)

Drugs in Sport

• Permitted - No warnings

Central Nervous System Disorders

• Headache
• Dizzyness

Cardiovascular Disorders

• Proarrhythmias
• QT interval prolongation
• Widening of the QRS complex 
• Atrioventricular block
• Bundle–branch block
• Bradycardia
• Sinus block
• Ventricular fibrillation
• Ventricular tachycardia
• Torsades de Pointes
• Severe heart failure
• Cardiogenic shock 
• Hypotension

Gastrointestinal Disorders

• Dry mouth
• Abdominal pain
• Nausea and vomiting
• Anorexia
• Diarrhoea
• Constipation

Hepatobiliary Disorders

• Acute hepatic ischemia
• Cholestatic jaundice

Genitourinary Disorders

• Dysuria
• Acute urinary retention
• Renal insufficiency

Endocrine and Metabolic Disorders

• Hypoglycaemia

Skin and Subcutaneous Tissue Disorders

• Rashes
• Sweating

Immune, Blood and Lymphatic System Disorders

• Neutropenia

Sensory Disorders

• Disorders of accommodation
• Diplopia

Others

• Atropine-like effects

• Antiarrhythmic agents
• Agents known to provoke ventricular arrhythmias
• Agents known to cause torsade de pointes
• QT prolonging agents
• CYP3A inducers
• Agents that decrease serum potassium
• Anticholinergic agents

• ECG
• Vital signs

Specific cases may require

• Urinary output
• Blood glucose

Disopyramide decreases membrane responsiveness, prolongs the effective refractory period and slows cells with augmented automaticity. Effective refractory period of the atrium is lengthened, effective refractory period of the atrioventricular node is shortened and conduction in accessory pathways is prolonged.

Capsules 100mg

• Rythmodan (Sanofi)