All of the following anti-arrhythmic drugs are from class Ic EXCEPT:
High-Yield Explanation
Ref: KDT, 6th ed. pg. 511Anti-arrhythmic drugsClassActionsDrugsI- (Na+)(Na+ channel blockers) Ia: Na++K+ channel blocking propertyQuinidine, Procainamide, DisopyramideIb: Na+&K+ channel opening propertyTocainide, Lidocaine, Phenytoin, MexiletineIc: no effect on K+ channelFlecainide, Encainide, PropafenoneII-(b)Antiadrenergic agents (b blockers)Propranolol, Esmolol, (Sotalol is Class III mainly)III- (K)Agents widening AP (Prolong repolarization and ERP)Ibutilide, Sotalol, Bretylium, Amiodarone, Dronadarone, DofetilideIV- (Ca+)Calcium channel blockersVerapamil, DiltiazemVDrugs with other mechanism of actionsMagnesium (DOC in torsades de pointes) Atropine: DOC for Bradycardia a and AV Block DigoxinAdenosine: DOC for PSVTNote: Class IA agents also have Class III property; propranolol has Class I action as well; sotalol and bretylium have both class II and class III actions.