Generic
Amiodarone Hydrochloride
6 brands available in the market
At a glance
Amiodarone Hydrochloride is an antiarrhythmic medication used for the treatment of serious heart rhythm disorders including ventricular fibrillation, ventricular tachycardia, atrial fibrillation and atrial flutter.
Description
Amiodarone Hydrochloride is a class III antiarrhythmic agent that inhibits stimulation, prolongs action potential and refractory period in myocardial tissues. It also decreases AV conduction and sinus node function. Sinus rate is reduced by 15-20%, and PR and QT intervals are increased. Amiodarone is a broad spectrum antiarrhythmic that delays cardiac repolarization and dilates blood vessels.
Indications
Ventricular fibrillation (VF); hemodynamically unstable ventricular tachycardia (VT); atrial fibrillation; atrial flutter; serious arrhythmias refractory to other therapy.
Therapeutic class
Potassium Channel Blockers
Pharmacological class
Class III Antiarrhythmic
Pharmacology
Amiodarone is a class III antiarrhythmic agent that prolongs action potential and refractory period in myocardial tissues. It decreases AV conduction and sinus node function. Sinus rate is reduced by 15-20%, and PR and QT intervals are increased. Amiodarone also dilates blood vessels, which may be beneficial in patients with congestive heart failure.
Mechanism of action
Amiodarone delays cardiac repolarization, prolongs action potential, and slows AV conduction, restoring normal heart rhythm in arrhythmias.
Dosage
Oral (Tablet): Loading dose: 800-1600 mg once daily (1-3 weeks); Intermediate dose: 600-800 mg/day (1 month); Maintenance dose: 200-400 mg once daily. Intravenous (IV): Initial load: 150 mg over 10 minutes (15 mg/min); Next: 1 mg/min for 6 hours; Then: 0.5 mg/min for 18 hours; Total 24 hours: 1000 mg; Maintenance infusion: 0.5 mg/min (up to 2-3 weeks).
Administration
May be taken with or without food (taking with food reduces stomach upset). Swallow tablets whole. For IV infusion: Dilute with 5% Dextrose; concentrations >2 mg/mL should be administered via central venous catheter.
Missed dose
If you miss a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and continue with your regular schedule. Do not double the dose.
Side effects
Common (>10%): Elevated liver enzymes (AST/ALT 3-20%), hypotension (16%), dizziness (3-40%), photosensitivity (10-75%), hypothyroidism (1-22%), constipation (10-33%). Common (1-10%): CHF (3%), bradycardia (3-5%), AV block (5%), hyperthyroidism (3-10%), visual disturbances (2-9%). Serious (rare): Pulmonary fibrosis, interstitial pneumonitis, hepatotoxicity, thyrotoxicity, ventricular arrhythmias.
Precautions & warnings
Arrhythmias may worsen, especially with QT-prolonging drugs. Hypotension and bradycardia may occur. Risk of liver toxicity; monitor liver function regularly. Monitor for pulmonary toxicity (cough, fever, shortness of breath). Photosensitivity; avoid excessive sun exposure. Corneal refractive laser surgery not recommended in patients on amiodarone. Monitor thyroid function regularly. Correct electrolyte imbalances before starting treatment.
Contraindications
Hypersensitivity to amiodarone or iodine; severe sinus node dysfunction; 2nd and 3rd degree heart block (without pacemaker); cardiogenic shock; pregnancy.
Drug interactions
Warfarin: Increased anticoagulant effect; warfarin dose should be reduced by approximately half. Digoxin: Increased plasma concentrations. Beta-blockers and calcium channel blockers: Additive effect (bradycardia). Cimetidine: May increase amiodarone serum levels. Rifampin: May decrease amiodarone serum levels. HMG-CoA reductase inhibitors: Increased risk of myopathy/rhabdomyolysis.
Food interactions
Information on alcohol consumption is not available; consult your doctor.
Use in pregnancy
Pregnancy Category: D. Amiodarone is generally not recommended during pregnancy; risk of fetal hypo or hyperthyroidism. Use only if clearly needed with medical advice.
Pregnancy Category: D — always consult a doctor before taking during pregnancy.
Use in lactation
Amiodarone is excreted into breast milk; use during breastfeeding is not recommended.
Pediatric use
Safety and efficacy in pediatric patients have not been established.
Geriatric use
Elderly patients should start at the lower end of the dosing range (higher risk of toxicity).
Renal / hepatic impairment
Renal impairment: No dose adjustment needed based on renal function (plasma clearance is not affected). Hepatic impairment: Dose reduction may be necessary; monitor liver function regularly.
Overdose effects
Overdose symptoms: bradycardia, hypotension, seizures, ventricular arrhythmias. Treatment: symptomatic and supportive measures; hemodialysis is not effective.
Storage conditions
Store below 30C, protected from light and moisture. Keep out of reach of children.
Chemical structure
C25H29I2NO3 (Molecular weight: 645.3 g/mol)