Amiodarone

Class III·Cardiovascular - Antiarrhythmics

Refractory VF/VT, atrial fibrillation (pharmacological cardioversion and maintenance)

Authority requiredPBSANTIARRHYTHMICCordarone X, Aratac, Rythmodan100 mg tablet+2

Max Dose

1200 mg/day

Half-life

50 Days

Toxicity

HIGH RISK

Thyroid

MONITOR

Rapid Summary

Overview

Incredibly potent, highly lipophilic antiarrhythmic. Extremely effective for chemical cardioversion and rhythm control, but riddled with severe, multi-organ toxicities.

Maximum Dose

Max 1200 mg/day (during acute loading phase only). Maintenance is 100-200 mg/day.

Clinical Focus

Amiodarone stays in the body for months after stopping. It interacts with almost everything and requires baseline tests for thyroid, lungs, and liver.

Bottom Line

Amiodarone is the most effective antiarrhythmic for life-threatening arrhythmias, but causes devastating multi-organ toxicity (thyroid, lung, liver, eyes) requiring lifelong monitoring.

Formulation & Access

Brand Names

Cordarone X, Aratac, Rythmodan

Oral Routes

Tablets (100 mg, 200 mg).

Parenteral

Ampoule (150 mg/3 mL) for IV infusion. Requires specific diluents (D5W).

Prescribing & PBS

Authority Required (PBS).

Indications & Use

Primary

PBSTGA

Refractory VF/VT, atrial fibrillation (pharmacological cardioversion and maintenance).

Clinical Place

The most effective antiarrhythmic available. The drug of choice for arrhythmias in patients with structural heart disease or HFrEF.

Quick reference

Class & Role

Class III — Incredibly potent, highly lipophilic antiarrhythmic.

Route / Formulation

Tablets (100 mg, 200 mg). (Cordarone X, Aratac, Rythmodan)

Usual Dose & Max

IV 300 mg bolus via central line (or large peripheral). Max 1200 mg/day (during acute loading phase only). Maintenance is 100-200 mg/day.

Key Indication Doses

Cardiac Arrest (VF/pVT): IV 300 mg bolus via central line (or large peripheral). Acute AF / Arrhythmia (IV): IV 300 mg over 1-2 hours via central line, followed by 900 mg over 24 hours. Oral Loading (AF): PO 400 mg TDS for 1 week, then 400 mg OD for 1 week, then maintenance. Maintenance: PO 100-200 mg OD.

Best Uses

Amiodarone is the most effective antiarrhythmic for life-threatening arrhythmias, but causes devastating multi-organ toxicity (thyroid, lung, liver, eyes) requiring lifelong monitoring.

Avoid / Cautions

Severe bradycardia, sick sinus syndrome, iodine allergy, existing thyroid dysfunction. Pregnancy Category C. Causes neonatal goitre/hypothyroidism.

Key Risks

Endocrine: Hypothyroidism or severe Hyperthyroidism (contains 37% iodine by weight). Respiratory: Pulmonary fibrosis / interstitial pneumonitis (can be fatal). Hepatic: Elevated transaminases, cirrhosis. Ocular / Derm: Corneal microdeposits (halos/glare), photosensitivity, slate-grey skin discoloration ('smurf skin').

Key Interactions

Potent inhibitor of CYP3A4, CYP2C9, and P-gp. Doubles the levels of Digoxin and Warfarin (halve their doses when starting amiodarone!). Increases statin toxicity. Beta-blockers, CCBs, and other QTc prolonging drugs.

Monitoring

Baseline and 6-monthly TFTs, LFTs, and U&E. Baseline CXR (for pulmonary fibrosis tracking). Annual optometry review. Monitor ECG for QTc prolongation and bradycardia.

Clinical Pearl

When you start Amiodarone on a patient taking Warfarin, you MUST preemptively halve their Warfarin dose, or they will bleed. The INR will spike dramatically.

Access

Authority requiredCordarone X, Aratac, Rythmodan100 mg tablet

Brand: Cordarone X, Aratac, Rythmodan
PBS status: Authority required
Formulation: Tablets (100 mg, 200 mg)

Amiodarone

Class III·Cardiovascular - Antiarrhythmics

Refractory VF/VT, atrial fibrillation (pharmacological cardioversion and maintenance)

Authority requiredPBSANTIARRHYTHMICCordarone X, Aratac, Rythmodan100 mg tablet+2

Max Dose

1200 mg/day

Half-life

50 Days

Toxicity

HIGH RISK

Thyroid

MONITOR

Rapid Summary

Overview

Incredibly potent, highly lipophilic antiarrhythmic. Extremely effective for chemical cardioversion and rhythm control, but riddled with severe, multi-organ toxicities.

Maximum Dose

Max 1200 mg/day (during acute loading phase only). Maintenance is 100-200 mg/day.

Clinical Focus

Amiodarone stays in the body for months after stopping. It interacts with almost everything and requires baseline tests for thyroid, lungs, and liver.

Bottom Line

Amiodarone is the most effective antiarrhythmic for life-threatening arrhythmias, but causes devastating multi-organ toxicity (thyroid, lung, liver, eyes) requiring lifelong monitoring.

Formulation & Access

Brand Names

Cordarone X, Aratac, Rythmodan

Oral Routes

Tablets (100 mg, 200 mg).

Parenteral

Ampoule (150 mg/3 mL) for IV infusion. Requires specific diluents (D5W).

Prescribing & PBS

Authority Required (PBS).

Indications & Use

Primary

PBSTGA

Refractory VF/VT, atrial fibrillation (pharmacological cardioversion and maintenance).

Clinical Place

The most effective antiarrhythmic available. The drug of choice for arrhythmias in patients with structural heart disease or HFrEF.

Quick reference

Class & Role

Class III — Incredibly potent, highly lipophilic antiarrhythmic.

Route / Formulation

Tablets (100 mg, 200 mg). (Cordarone X, Aratac, Rythmodan)

Usual Dose & Max

IV 300 mg bolus via central line (or large peripheral). Max 1200 mg/day (during acute loading phase only). Maintenance is 100-200 mg/day.

Key Indication Doses

Best Uses

Amiodarone is the most effective antiarrhythmic for life-threatening arrhythmias, but causes devastating multi-organ toxicity (thyroid, lung, liver, eyes) requiring lifelong monitoring.

Avoid / Cautions

Severe bradycardia, sick sinus syndrome, iodine allergy, existing thyroid dysfunction. Pregnancy Category C. Causes neonatal goitre/hypothyroidism.

Key Risks

Key Interactions

Monitoring

Baseline and 6-monthly TFTs, LFTs, and U&E. Baseline CXR (for pulmonary fibrosis tracking). Annual optometry review. Monitor ECG for QTc prolongation and bradycardia.

Clinical Pearl

When you start Amiodarone on a patient taking Warfarin, you MUST preemptively halve their Warfarin dose, or they will bleed. The INR will spike dramatically.

Access

Authority requiredCordarone X, Aratac, Rythmodan100 mg tablet

Brand: Cordarone X, Aratac, Rythmodan
PBS status: Authority required
Formulation: Tablets (100 mg, 200 mg)