Amiodarone prolonged the refractory period of the heart with out causing of the blockade of the sodium.
- It can be given orally and parenterally.it is absorbed from the intestine, widely distributed and mainly deposited in the adipose tissue is metabolized in the liver and excreted in the bile and faeces. when given for a prolonged period, its plasma half life is about 54 days due to its slow elimination from the body.
- Amiodarone treats and prevents abnormal heartbeats by working inside cells to control muscle contractions in the heart. This helps your heart beat normally.
Clinical uses:
- Amiodarone is a powerful antiarrhythmic drug which is used for the treatment of ventricular arrhythmias.
- It may be used for the prevention of ventricular response in cases of atrial fibrillation and atrial flutter.
- It may restore sinus rhythm in cases of atrial fibrillation and flutter.also it may be used for the maintenance of sinus rhythm in cases of atrial fibrillation and flutter after cardioversion.
- It may be effective for the arrhythmias of wolf-Parkinson-white syndrome.
Adverse effects:
- Most common side effects includes Nausea,Vomiting,constipation,tremors,fatigue,lack of cordination,headache,stomach pain,sleep disturbances etc
- Bradycardia and heart block can occur.
- Ventricular arrhythmia can occur with amiodarone.
- Microdeposits can occur on the cornea that can cause photophobia and visual halos, but these are reversible when treatment with amiodarone is stopped.
- Both hypo and hyperthyroidism can occur with it.Thus thyroid function tests should be done both before and after treatment with amiodarone.
- Rarely, hepatitis and pulmonary fibrosis can occur with it.
Drug interaction
- It increases the effects of digoxin and warfarin.
- It increases the depressant effects of beta blockers and calcium channel blockers on the sinoatrial node and AV node.