Amiodarone hydrochloride (Amiodarone HCl) is an antianginal and class III antiarrhythmic drug. It increases the duration of ventricular and atrial muscle action by inhibiting POTASSIUM CHANNELS and VOLTAGE-GATED SODIUM CHANNELS. There is a resulting decrease in heart rate and in vascular resistance.

K+-ATP channel:19.1 μM

Amiodarone (AM) inhibits the intracellular conversion from thyroxine (T4) to triiodothyronine (T3) via 5'-deiodination (5'DI) without affecting the intracellular conversion from T4 to reverse T3 (rT3).1.25-25 mg/kg Amiodarone in the AV node and in anaesthetized dogs resulted in a decrease in sinus rate, a prolongation of the AV node effective and functional occlusion of the AV node, as well as frequency-dependent conduction delays. 50 mg/kg daily for 3-4 weeks Amiodarone in rabbit ventricular myocytes resulted in a significant reduction in iK and ito current densities without affecting ICA and IK1 densities.

Amiodarone penetrates deeply into the lipid matrix of the membrane and is released very slowly from cardiac tissue during washout.Amiodarone inhibits fast sodium channels as well as slow calcium channels.Amiodarone also has non-competitive antiarrhythmic effects and regulates thyroid function and phospholipid metabolism.44-88 μM Amiodarone inhibits Vmax of guinea pig papillary muscle without affecting normal hematopoietic stem cells.44-88 μM Amiodarone inhibits Vmax of guinea pig papillary muscle without affecting normal hematopoietic stem cells. Amiodarone inhibits Vmax in papillary muscle without affecting the resting membrane potential, and this Vmax inhibition is potentiated in a frequency- or use-dependent manner as is the case with class I antiarrhythmic drugs.50-88 μM Amiodarone inhibits depolarization-induced spontaneous action potentials (aberrant automaticity) in ventricular myocardium and Purkinje fibers.50-88 μM Amiodarone inhibits depolarization induced action potentials (aberrant automaticity) in human ventricular muscle.