SOTALOL-WGR

What it is

SOTALOL-WGR contains sotalol hydrochloride 80 mg or 160 mg. The 80 mg tablets are light blue, biconvex, capsule shaped tablets, plain on one side and engraved 'S', '80' and a break bar on the other side, while the 160 mg tablets are light blue, biconvex, capsule shaped tablets, plain on one side and engraved 'S', '160' and a break bar on the other side.

Approved indications

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

Dosing overview

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 two 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 of SOTALOL-WGR should be adjusted gradually allowing 2–3 days between dosing increments in order to attain steady-state, and to allow monitoring of QT intervals. Because sotalol is primarily excreted by the kidneys, a dosage adjustment should be made in patients with impaired renal function.

Key safety warnings

The most dangerous adverse effect of antiarrhythmic drugs is the aggravation of preexisting arrhythmias or the provocation of new arrhythmias. The 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 (such as from diuretic use), high plasma drug concentrations (from overdosage or renal insufficiency), and with the concomitant use of sotalol and other medication such as antidepressants and Class I antiarrhythmics which have been associated with torsades de pointes. Females appear to be at increased risk of developing torsades de pointes. During clinical trials, 4.3% of 3257 patients with arrhythmias experienced a new or worsened ventricular arrhythmia, including sustained ventricular tachycardia (approximately 1%) and torsades de pointes (2.4%). In addition, in approximately 1% of patients, deaths were considered possibly drug-related. 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. Moreover, patients with congestive heart failure have a higher risk of torsade de pointes. Sotalol should not be used in patients with hypokalaemia or hypomagnesaemia prior to correction of imbalance; these conditions can exaggerate the degree of QT prolongation and increase the potential for torsades de pointes. Special attention should be given to electrolyte and acid-base balance in patients experiencing severe or prolonged diarrhoea or patients receiving concomitant magnesium- and/or potassium-depleting drugs.

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 AV block or sick sinus syndrome unless a functioning pacemaker is present. Uncontrolled congestive heart failure, severe renal impairment (CrCl < 10 mL per minute), and congenital or acquired long QT syndromes. Hypersensitivity to sotalol hydrochloride, other beta blockers, sulfonamides or the excipients. Hypomagnesaemia, hypotension, metabolic acidosis, torsades de pointes, and hypokalaemia.

Regulatory history

SOTALOL-WGR 80 mg and 160 mg tablets were first listed on the ARTG on 4 May 2020.