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Generic Name: amiodarone (oral) (A mi OH da rone)
Brand Name: Pacerone

Medically reviewed on May 26, 2017

What is Pacerone?

Pacerone affects the rhythm of your heartbeats.

Pacerone is used to help keep the heart beating normally in people with life-threatening heart rhythm disorders of the ventricles (the lower chambers of the heart that allow blood to flow out of the heart). This medicine is used to treat ventricular tachycardia or ventricular fibrillation.

Pacerone is for use only in treating life-threatening heart rhythm disorders.

Pacerone may also be used for purposes not listed in this medication guide.

Important Information

Pacerone is for use only in treating life-threatening heart rhythm disorders.

You should not take Pacerone if you are allergic to Pacerone or iodine, or if you have 2nd- or 3rd-degree "AV block" (unless you have a pacemaker), a history of slow heartbeats, or if your heart cannot pump blood properly.

Pacerone can cause dangerous side effects on your heart, liver, lungs, or thyroid.

Call your doctor or get medical help at once if you have: chest pain, fast or pounding heartbeats, trouble breathing, upper stomach pain, vomiting, dark urine, jaundice (yellowing of the skin or eyes), or if you cough up blood.

Tell your doctor if you have signs of a thyroid problem, such as weight changes, extreme tiredness, dry skin, thinning hair, feeling too hot or too cold, irregular menstrual periods, or swelling in your neck (goiter).

Before taking this medicine

You should not use this medicine if you are allergic to Pacerone or iodine, or if you have:

  • a serious heart condition called "AV block" (2nd or 3rd degree), unless you have a pacemaker;

  • a history of slow heartbeats that have caused you to faint; or

  • if your heart cannot pump blood properly.

Pacerone can cause dangerous side effects on your heart, liver, lungs, or thyroid.

To make sure Pacerone is safe for you, tell your doctor if you have ever had:

  • asthma or another lung disorder;

  • liver disease;

  • a thyroid disorder;

  • vision problems;

  • high or low blood pressure;

  • an electrolyte imbalance (such as low levels of potassium or magnesium in your blood); or

  • if you have a pacemaker or defibrillator implanted in your chest.

Do not use Pacerone if you are pregnant. Taking this medicine during pregnancy can harm the unborn baby or cause thyroid problems or abnormal heartbeats after the baby is born. This medicine may also affect the child's growth or development (speech, movement, academic skills) later in life. Use effective birth control to prevent pregnancy during treatment.

Amiodarone can pass into breast milk and may harm a nursing baby. You should not breast-feed while using this medicine.

How should I take Pacerone?

Follow all directions on your prescription label. Do not take Pacerone in larger or smaller amounts or for longer than recommended. You will receive your first few doses in a hospital setting, where your heart rhythm can be monitored.

If you have been taking another heart rhythm medicine, you may need to gradually stop taking it when you start using Pacerone. Follow your doctor's dosing instructions very carefully.

You may take Pacerone with or without food, but take it the same way each time.

It may take up to 2 weeks before your heart rhythm improves. Keep using the medicine as directed even if you feel well.

While using Pacerone, you will need frequent medical tests and chest x-rays to check your thyroid, vision, lungs, and liver function. This medicine can have long lasting effects on your body. You may need medical tests for several months after you stop using this medicine.

If you need surgery (including laser eye surgery), tell the surgeon ahead of time that you are using Pacerone. You may need to stop using the medicine for a short time.

Pacerone can cause unusual results with certain medical tests. Tell any doctor who treats you that you are using this medicine.

Store at room temperature away from moisture, heat, and light.

Read all patient information, medication guides, and instruction sheets provided to you. Ask your doctor or pharmacist if you have any questions.

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222. An overdose of Pacerone can be fatal.

Overdose symptoms may include weakness, slow heart rate, feeling light-headed, or loss of consciousness.

What should I avoid while taking amiodarone?

Grapefruit and grapefruit juice may interact with Pacerone and lead to unwanted side effects. Avoid the use of grapefruit products while taking this medicine.

Avoid exposure to sunlight or tanning beds. Pacerone can make you sunburn more easily. Wear protective clothing and use sunscreen (SPF 30 or higher) when you are outdoors.

Pacerone may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.

Pacerone side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Pacerone takes a long time to completely clear from your body. You may continue to have side effects from this medicine after you stop using it. It could take up to several months for the medicine to completely clear from your body.

Call your doctor at once if you have any of these side effects, even if they occur up to several months after you stop using Pacerone:

  • wheezing, cough, chest pain, coughing up blood, breathing problems that get worse;

  • a new or a worsening irregular heartbeat pattern (fast, slow, or pounding heartbeats);

  • a light-headed feeling, like you might pass out;

  • blurred vision, seeing halos around lights, vision loss, headache or pain behind your eyes, sometimes with vomiting;

  • liver problems--nausea, upper stomach pain, itching, tired feeling, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes);

  • nerve problems--loss of coordination, muscle weakness, uncontrolled muscle movement, or numbness and tingling in your hands or lower legs;

  • signs of overactive thyroid--weight loss, thinning hair, feeling too hot or too cold, increased sweating, irregular menstrual periods, swelling in your neck (goiter); or

  • signs of underactive thyroid--extreme tired feeling, dry skin, joint pain or stiffness, muscle pain or weakness, hoarse voice, feeling more sensitive to cold temperatures, weight gain.

Common side effects may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect Pacerone?

Pacerone takes a long time to completely clear from your body. Drug interactions are possible for up to several months after you stop using this medicine. Talk to your doctor before taking any medication during this time. Keep track of how long it has been since your last dose of amiodarone.

Many drugs can interact with Pacerone. Not all possible interactions are listed here. Tell your doctor about all your current medicines and any you start or stop using, especially:

  • an antibiotic or antifungal medicine;

  • an antidepressant;

  • anti-malaria medicine;

  • antiviral medicine to treat hepatitis, HIV, or AIDS;

  • asthma inhalers;

  • a blood thinner;

  • cancer medicines;

  • a diuretic or "water pill";

  • heart or blood pressure medication;

  • medicine to prevent vomiting;

  • medicine to treat mental illness; or

  • "statin" cholesterol medicine (Lipitor, Zocor, Vytorin, and others).

This list is not complete and many other drugs can interact with Pacerone. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Give a list of all your medicines to any healthcare provider who treats you.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.