Amiodarone

Amiodarone is an active substance belonging to the class III antiarrhythmic agents, used as a second-line treatment for cardiac arrhythmias.‍‍‍‍‍‍​​​‍​​​​​​ Its effects are based, among other mechanisms, on the inhibition of potassium efflux during phase III of the action potential in myocardial tissue. Tablets are taken with or after a meal. Amiodarone is a substrate of CYP3A4 and CYP2C8 and has a high potential for drug interactions. It has a very long half-life of 20 to 100 days. The most common possible adverse effects include corneal microdeposits, gastrointestinal disturbances, metallic taste, elevated transaminases, photosensitization, and sunburn. Amiodarone prolongs the QT interval and can itself cause cardiac arrhythmias. Numerous additional adverse effects are possible, affecting among others the lungs, thyroid gland, and nervous system. Amiodarone (ATC C01BD01) has antiarrhythmic properties. Its effects are based on the inhibition of potassium efflux during phase III of the action potential in myocardial tissue. This prolongs the repolarization duration and the refractory period of the action potential. Amiodarone additionally possesses sympatholytic properties. It has a very long half-life of up to 20 to 100 days. Mechanisms of action of antiarrhythmic agents in the action potential of cardiac muscle cells (myocytes), click to enlarge. Illustration © PharmaWiki