Adult Supraventricular arrhythmia Initially 50 mg bd. If required, dose may be increased to max of 300 mg daily.
Ventricular arrhythmia Initially 100 mg bd. Max daily dose: 400 mg. Progressively adjust dose to lowest level which maintains control of the arrhythmia after 3-5 days.
Renal impairment (CrCl ≤35 mL/min/1.73 m2) Max initial dose: 100 mg daily or 50 mg bd.