APX-SOTALOL

What it is

APX-SOTALOL contains sotalol hydrochloride and is available in tablets of 80 mg or 160 mg strength.

Approved indications

— Prevention and treatment of supraventricular arrhythmias — Prevention and treatment of ventricular arrhythmias

Dosing overview

APX-SOTALOL is administered orally for the prevention and treatment of arrhythmias. The recommended initial oral dosing schedule is 160 mg daily, given in two divided doses at approximately 12 hour intervals. This dose may be increased, if necessary, after appropriate evaluation to 240 or 320 mg per day. In most patients, a therapeutic response is obtained at a total daily dose of 160–320 mg per day, given in 2 divided doses. Some patients with life-threatening refractory ventricular arrhythmias may require doses as high as 480–640 mg per day; however, these doses should only be prescribed when the potential benefit outweighs the increased risk of adverse events particularly proarrhythmias. Oral dosage should be adjusted gradually allowing 2–3 days between dosing increments in order to attain steady-state, and to allow monitoring of QT intervals.

Key safety warnings

The most dangerous adverse effect of antiarrhythmic drugs is the aggravation of preexisting arrhythmias or the provocation of new arrhythmias. Drugs that prolong the QT interval may cause torsades de pointes, a polymorphic ventricular tachycardia associated with prolongation of the QT interval. The risk of torsades de pointes is associated with the prolongation of the QT interval, reduction in heart rate, reduction in serum potassium and magnesium (for example, as a consequence of diuretic use), high plasma drug concentrations (for example, as a consequence of overdosage or renal insufficiency), and with the concomitant use of sotalol and other medication such as antidepressants and Class 1 antiarrhythmics which have been associated with torsades de pointes. Females appear to be at increased risk of developing torsades de pointes. Beta-blockade depresses myocardial contractility and may precipitate cardiac failure in some patients with a history of cardiac failure, chronic myocardial insufficiency, or unsuspected cardiomyopathy. Patients with congestive heart failure have a higher risk of torsade de pointes. Care should be taken if beta-blockers have to be discontinued abruptly in patients with coronary artery disease. Hypersensitivity to catecholamines is observed in patients withdrawn from beta-blocker therapy. Severe exacerbation of angina pectoris and precipitation of myocardial infarction and ventricular arrhythmias have occurred following abrupt discontinuation of beta-blockade in patients with ischaemic heart disease.

Contraindications

Bronchospasm (such as bronchial asthma or chronic obstructive airway disease) and allergic disorders (including allergic rhinitis) which may suggest a predisposition to bronchospasm. Sinus bradycardia (less than 45–50 beats per minute) and second and third degree atrioventricular block or sick sinus syndrome unless a functioning pacemaker is present. Uncontrolled congestive heart failure and severe renal impairment (CrCl < 10 mL per minute). Congenital or acquired long QT syndromes. Hypomagnesaemia and hypotension. Hypokalaemia.

Regulatory history

APX-SOTALOL sotalol hydrochloride 80 mg tablets were first listed on the Australian Register of Therapeutic Goods on 4 May 2020, and APX-SOTALOL sotalol hydrochloride 160 mg tablets were first listed on the same date.