What are the contraindications for Sotalol?

Sotalol Contraindications

Sotalol is contraindicated in patients with sinus bradycardia (<50 bpm during waking hours), sick sinus syndrome or second and third degree AV block (unless a functioning pacemaker is present), congenital or acquired long QT syndromes, baseline QT interval >450 msec, cardiogenic shock, uncontrolled heart failure, hypokalemia (<4 meq/L), creatinine clearance <40 mL/min, bronchial asthma and previous evidence of hypersensitivity to sotalol. 1

Cardiac Contraindications

• Bradyarrhythmias: Sotalol is contraindicated in patients with sinus bradycardia (<50 bpm during waking hours), sick sinus syndrome, or second/third-degree AV block without a functioning pacemaker due to its beta-blocking properties that can further slow conduction 1
• Prolonged QT interval: Baseline QT interval >450 msec is an absolute contraindication as sotalol prolongs cardiac repolarization and can precipitate torsades de pointes 1
• Congenital or acquired long QT syndromes: These patients are at high risk for torsades de pointes with sotalol administration 1
• Cardiogenic shock: Beta-blocking properties of sotalol can worsen hypotension and cardiac output in shock states 1
• Uncontrolled heart failure: Sotalol's negative inotropic effects can worsen heart failure symptoms 1, 2

Electrolyte Abnormalities

• Hypokalemia (<4 meq/L): Low potassium levels increase the risk of QT prolongation and torsades de pointes with sotalol 1, 3
• Correction of electrolyte abnormalities: Hypokalemia must be corrected before initiating sotalol therapy to reduce proarrhythmic risk 1

Renal Function Considerations

• Renal impairment: Creatinine clearance <40 mL/min is an absolute contraindication for sotalol use 1
• Dose adjustment: In patients with creatinine clearance between 40-60 mL/min, sotalol should be administered once daily rather than twice daily 1

Respiratory Contraindications

• Bronchial asthma: Sotalol is contraindicated due to its non-selective beta-blocking properties that can trigger bronchospasm 1

Other Contraindications

• Hypersensitivity: Previous evidence of hypersensitivity to sotalol is a contraindication 1
• Pregnancy considerations: Use during pregnancy should be carefully evaluated due to potential fetal risks 4

Special Precautions

• Proarrhythmic potential: Sotalol has a risk of proarrhythmia, particularly torsades de pointes, which occurs more commonly in women and heart failure patients 2, 3
• Initiation requirements: Therapy must be initiated with continuous ECG monitoring for a minimum of 3 days on the maintenance dose 1
• QT monitoring: QT interval should be monitored 2-4 hours after each dose during initiation and titration 1
• Discontinuation: If QT interval is ≥520 msec while on the lowest maintenance dose (80 mg), the drug should be discontinued 1

Contraindications in Specific Clinical Scenarios

• Digitalis toxicity: Electrical cardioversion is contraindicated in patients with digitalis toxicity or hypokalemia when using sotalol 5
• Structural heart disease: Unlike flecainide and propafenone which are contraindicated in structural heart disease, sotalol can be used in patients with structural heart disease or ischemic heart disease, but with careful monitoring 5

Common Pitfalls in Sotalol Prescribing

• Failure to monitor QT interval: Not checking QT interval before and during therapy is a dangerous oversight 1
• Inadequate renal function assessment: Calculating creatinine clearance is essential before initiating therapy 1
• Outpatient initiation: Hospital admission is warranted for initiation of sotalol therapy due to the 20.8% incidence of significant arrhythmia complications detected during monitoring 3
• Drug interactions: Medications that prolong QT interval should be avoided in combination with sotalol 4