Amiodarone: what it does and what to watch for

Amiodarone is a strong antiarrhythmic drug used to treat dangerous heart rhythms like ventricular tachycardia and to control atrial fibrillation when other drugs fail. It works slowly and stays in the body a long time, so the effects (and side effects) can last for weeks or months after you stop taking it. Because of that, doctors monitor patients closely while on the drug.

Who gets amiodarone and how it’s given

Doctors usually choose amiodarone for serious or persistent arrhythmias, or when other medicines aren’t safe or effective. It comes as tablets for long-term use and as an intravenous form for emergencies in the hospital. Typical oral plans start with a higher loading dose for several days to weeks, then taper to a lower maintenance dose—commonly around 200 mg daily— but your exact dose will depend on the problem and your doctor’s plan.

Key side effects and what to report

Amiodarone can cause several important side effects. The ones to know right away: new or worsening shortness of breath or cough (could mean lung toxicity), yellowing eyes or dark urine (liver problems), sudden weight changes, or tremors and vision changes. It can also affect your thyroid—either overactive or underactive—and cause skin sensitivity to sunlight and a bluish skin tint with long use. If you feel faint, notice a very slow heartbeat, or have new chest pain, contact your doctor immediately.

Some side effects are common but less urgent: nausea, constipation, or mild skin rash. Don’t stop the drug suddenly without talking to your doctor—abrupt withdrawal can make arrhythmias worse.

Because amiodarone has a very long half-life, side effects may appear late and take time to clear once the drug is reduced or stopped.

Monitoring and tests you’ll need

Before starting amiodarone, expect baseline tests: ECG, chest X-ray or lung function if suggested, liver blood tests, and thyroid function tests. During treatment, your doctor will repeat thyroid and liver tests regularly (often every 3–6 months) and may schedule periodic chest imaging and eye checks. Regular heart rhythm checks (ECG) are needed, especially if you take other heart drugs.

Drug interactions matter. Amiodarone raises levels of warfarin and digoxin, so those doses often need lowering. It can increase statin levels (higher myopathy risk), and combining it with some beta-blockers or calcium channel blockers can slow your heart too much. Also watch out for other QT-prolonging drugs—combined effects can be dangerous.

Practical tips: use sunscreen and protective clothing, tell any new doctor or pharmacist you take amiodarone, and carry a list of your medications. If you’re pregnant or planning pregnancy, discuss alternatives—amiodarone is generally avoided because of risks to the baby.

If you have questions about how amiodarone fits into your care, talk to your cardiologist or pharmacist. They can explain specific dosing, monitoring schedules, and how to manage interactions with other medicines you take.