Antiarrhythmic Drugs and Associated Arrhythmias.
Class I: Fast sodium (Na) channel blockers:
- Ia - Quinidine, procainamide, disopyramide (depress phase 0, prolonging repolarization)
- Ib - Lidocaine, phenytoin, mexiletine (depress phase 0 selectively in abnormal/ischemic tissue, shorten repolarization)
- Ic - Flecainide, propafenone, moricizine (markedly depress phase 0, minimal effect on repolarization)
Class II: Beta blockers (partial list).Decrease slope of phase 4:
- Propranolol
- Esmolol
- Timolol
- Metoprolol
- Atenolol
Class III: Potassium (K) channel blockers:
- Amiodarone (prolongs phase 3; also acts on phases 1, 2, and 4)
- Sotalol (prolongs phase 3, decreases slope of phase 4)
- Ibutilide (prolongs phase 3)
- Dofetilide (prolongs phase 3)
Class IV: Slow calcium (Ca) channel blockers. Prolong phase 2:
- Verapamil
- Diltiazem
Class V: Variable mechanism:
- Adenosine
- Digoxin
- Magnesium sulfate
