| Contraindicated in children with hypersensitivity to procaine and related drugs; In those with complete, second-, or third-degree heart block in the absence of an artificial pacemaker; and in children with myasthenia gravis or systemic lupus erythematosus. Also contraindicated in children with atypical ventricular tachycardia (torsades de pointes) because procainamide may aggravate this condition. |