Amiodarone

What is Amiodarone?

Amiodarone is a medication available under brand names such as Cordarone, Pacerone, and Nexterone (an IV formulation), as well as in generic form. It belongs to a class of drugs known as antiarrhythmics, specifically a Class III antiarrhythmic, though it also has properties of several other antiarrhythmic classes.

Amiodarone is approved for:

• Treating certain life-threatening ventricular arrhythmias, such as recurrent ventricular fibrillation or recurrent, hemodynamically unstable ventricular tachycardia, when other treatments have not been effective or tolerated
• It is also widely used, including off-label in some cases, for managing atrial fibrillation and atrial flutter, and other supraventricular arrhythmias, particularly in patients with underlying structural heart disease where other antiarrhythmics may be less suitable

Amiodarone is available in the following formulations:

• Oral tablets (commonly available in 100 mg, 200 mg, and 400 mg strengths)
• Intravenous (IV) solution, used in hospital or emergency settings for acute, life-threatening arrhythmias

What is the Recommended Dosage of Amiodarone?

There is no single “correct” dose of amiodarone for everyone. The right dose depends on several individual factors, including:

• The specific arrhythmia being treated and its severity
• Whether a loading dose is needed to build up levels quickly, followed by a lower maintenance dose
• The patient’s age
• Liver function
• Other medications currently being taken
• Long-term tolerability, since amiodarone accumulates in body tissues over time and its side effect profile is closely tied to cumulative dose and duration of use

Available Dosage Forms

Amiodarone is available as oral tablets, often started with a higher loading dose over days to weeks, followed by a lower long-term maintenance dose, as well as an IV formulation used in acute settings.

Important Note on Dosing

Exact dosing instructions are not provided on this page because appropriate dosing must be determined individually, and because amiodarone’s dosing strategy (loading versus maintenance) and long half-life make careful, ongoing specialist management essential. Patients should:

• Follow the exact dose and schedule prescribed by their licensed medical specialist
• Never adjust the dose on their own
• Attend all recommended monitoring appointments (see Section 7), since amiodarone requires more extensive long-term monitoring than most other antiarrhythmics
• Never stop taking amiodarone abruptly without consulting their prescriber
• Ask their prescriber or pharmacist if dosing instructions are unclear

How Amiodarone Works

Amiodarone works through several mechanisms, primarily by blocking potassium channels in heart muscle cells, which prolongs the time it takes for heart cells to electrically “reset” between beats. It also has effects on sodium channels, calcium channels, and blocks some of the heart’s response to certain stress hormones (a mild beta-blocking-like effect).

In simple terms: amiodarone helps stabilize the heart’s electrical activity through multiple pathways at once, which can help control or prevent serious, rapid, or irregular heart rhythms, particularly in patients with underlying heart disease where other antiarrhythmics may not be appropriate or effective.

Amiodarone manages the symptoms and episodes of certain heart rhythm disorders; it does not cure the underlying heart condition causing the arrhythmia, and because of its unique combination of effectiveness and significant long-term side effect risks (see Section 7), it requires close, ongoing specialist supervision throughout treatment.

Is a Prescription Required to Buy Amiodarone Online?

Yes. Amiodarone is a prescription-only medication in the United States and most other countries.

Before starting amiodarone, patients should consult a licensed medical specialist, such as:

• A cardiologist, ideally one with expertise in heart rhythm disorders (electrophysiologist)

Important Safety Warning

Patients should be cautious of websites offering amiodarone without a prescription. These may include:

• Counterfeit medications with incorrect, unsafe, or no active ingredient
• Products not manufactured under proper quality and safety standards, which is a particular concern for a medication requiring precise dosing and extensive monitoring

Always obtain amiodarone from a licensed pharmacy, and only after being evaluated and prescribed by a qualified healthcare provider who can coordinate the extensive monitoring this medication requires.

Side Effects of Amiodarone

Common Side Effects

These are generally mild and may resolve on their own:

• Nausea, loss of appetite, or constipation, particularly during loading doses
• Fatigue or general tiredness
• Tremor or unsteadiness
• Increased sensitivity to sunlight, sometimes with a blue-gray skin discoloration with long-term use

Serious Side Effects

Amiodarone is associated with a wider range of potentially serious long-term side effects than most other antiarrhythmic medications, related to its accumulation in body tissues. Seek immediate medical attention if any of the following occur:

• Signs of lung problems, such as new or worsening shortness of breath, persistent cough, or fever, which may indicate a rare but serious lung toxicity that can occur with amiodarone
• Signs of liver problems, such as yellowing of the skin or eyes, dark urine, severe fatigue, loss of appetite, or upper abdominal pain
• Signs of thyroid problems, such as unexplained weight changes, heat or cold intolerance, changes in energy level, or new heart rhythm changes, since amiodarone can cause either an underactive or overactive thyroid
• Vision changes, since amiodarone can cause deposits in the cornea (usually not affecting vision significantly) and, rarely, optic nerve problems that can affect vision
• New or worsening heart rhythm problems, or a very slow heart rate
• Signs of an allergic reaction, such as swelling of the face, lips, tongue, or throat, hives, or difficulty breathing

This list is not exhaustive. Patients experiencing any unusual or concerning symptoms, especially breathing changes, should contact their prescriber promptly.

Drug Interactions

Amiodarone has an unusually large number of significant drug interactions, partly because it strongly affects several liver enzymes. Patients should tell their prescriber about all medications and products they use, including:

• Warfarin, since amiodarone can significantly increase its blood-thinning effect, often requiring a warfarin dose reduction and closer INR monitoring
• Digoxin, since amiodarone can raise digoxin levels significantly
• Other antiarrhythmic medications, since combined use can increase the risk of serious rhythm disturbances
• Statins, particularly simvastatin, since amiodarone can raise statin levels and increase the risk of muscle-related side effects
• Certain medications that prolong the QT interval, since combining these with amiodarone can increase the risk of dangerous heart rhythm disturbances
• Grapefruit juice, which can increase amiodarone levels
• Beta-blockers and certain calcium channel blockers, since combined use may excessively slow the heart

Patients should provide their licensed medical specialist and pharmacist with a complete and current list of all prescription drugs, OTC medications, vitamins, and herbal supplements before starting amiodarone, given how extensively this medication interacts with others.

Safety & Important Considerations

• Lung toxicity: Amiodarone carries a risk of serious, sometimes fatal, lung toxicity (pulmonary toxicity); baseline and periodic chest X-rays and lung function tests are commonly part of monitoring
• Liver toxicity: Amiodarone can cause liver damage; liver function tests are typically checked before starting and periodically during treatment
• Thyroid effects: Amiodarone contains iodine and can cause either an underactive or overactive thyroid; thyroid function tests are typically checked before starting and periodically during treatment
• Eye effects: Corneal deposits are common with long-term use and usually do not affect vision, but regular eye examinations may be recommended; rare optic nerve problems can affect vision more seriously
• Long half-life: Amiodarone remains in the body for weeks to months after stopping, meaning side effects and drug interactions can persist or emerge even after discontinuation
• Proarrhythmia risk: Like other antiarrhythmics, amiodarone carries some risk of causing new or worsened heart rhythm problems, though generally considered lower than some other antiarrhythmics in patients with structural heart disease
• Sun sensitivity: Patients should use sun protection, as amiodarone increases sensitivity to sunlight and can cause a blue-gray skin discoloration with prolonged use
• Pregnancy and breastfeeding: Amiodarone can cause harm to a developing fetus and passes into breast milk; it should only be used during pregnancy or breastfeeding if the potential benefit clearly justifies the risk, as determined by a specialist
• Age-related considerations: Older adults may be more sensitive to side effects and often require closer monitoring
• FDA boxed warning: Amiodarone carries boxed warnings regarding the risk of serious, sometimes fatal, toxicities affecting the lungs, liver, and heart rhythm, emphasizing that it should generally be reserved for life-threatening arrhythmias when other treatments have failed or are not tolerated
• Monitoring requirements: Amiodarone requires more extensive ongoing monitoring than most other antiarrhythmics, typically including periodic liver function tests, thyroid function tests, chest X-rays or lung function tests, eye examinations, and ECGs

This medication should only be used for its approved purpose, with the extensive monitoring required, as determined by a licensed specialist.

Who This Medication Is For

Amiodarone is generally intended for:

• Adults with life-threatening ventricular arrhythmias who have not responded to, or cannot tolerate, other treatments
• Adults with atrial fibrillation, atrial flutter, or other arrhythmias, particularly those with underlying structural heart disease where other antiarrhythmics may be less suitable
• Patients who have been evaluated by a licensed cardiologist or electrophysiologist and are able to participate in the extensive monitoring this medication requires

Use should always follow an appropriate clinical evaluation and a specialist’s recommendation, given amiodarone’s significant long-term risk profile.

Who Should Not Take Amiodarone

Amiodarone may not be appropriate for individuals who:

• Have severe underlying sinus node disease causing severe bradycardia, or significant heart block, without an appropriately functioning pacemaker
• Have a known allergy to amiodarone, iodine, or any ingredient in the product
• Have cardiogenic shock
• Have severe, active thyroid disease, without careful specialist management
• Have significant pre-existing lung disease, without careful specialist evaluation of the risks and benefits

This is not a complete list. A full medical history review by a licensed specialist is necessary to determine if amiodarone is safe and appropriate.

What to Do If You Miss a Dose

• Take the missed dose as soon as remembered, unless it is close to the time of the next scheduled dose, in which case the missed dose should generally be skipped
• Do not double up or take an extra dose to make up for a missed one
• Try to take amiodarone at the same time(s) each day to maintain consistent rhythm control
• Do not stop taking amiodarone on your own, even if a dose is missed occasionally, without consulting a prescriber
• Contact a licensed medical specialist if there is any uncertainty about the dosing schedule

Related medications to Amiodarone

Other medications used for arrhythmias, depending on the specific type of arrhythmia, presence of structural heart disease, and tolerability, include:

• Sotalol or dofetilide, other antiarrhythmics sometimes used in patients with structural heart disease
• Flecainide or propafenone, generally reserved for patients without significant structural heart disease
• Dronedarone, a related medication with a shorter half-life and different (though still significant) side effect profile
• Beta-blockers or calcium channel blockers, for certain arrhythmias
• Catheter ablation, a non-medication procedural option for certain arrhythmias

Switching between treatments should only be done in consultation with a licensed cardiologist or electrophysiologist, who can weigh factors such as the specific arrhythmia, presence of structural heart disease, and the significant long-term monitoring amiodarone requires.

Storage Instructions

• Store at room temperature, generally between 68°F and 77°F (20°C to 25°C), unless otherwise directed on the packaging
• Protect from light, since amiodarone tablets can be sensitive to light exposure
• Keep away from excess heat and moisture
• Store in the original packaging or container until ready to use
• Keep out of reach of children and pets
• Dispose of expired or unused medication according to local guidelines or pharmacist instructions

Disclaimer:

This page is for educational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Patients must consult a licensed cardiologist or electrophysiologist before starting, changing, or stopping treatment with amiodarone. Treatment decisions, including the extensive monitoring this medication requires, must be based on a full clinical evaluation by a qualified specialist.