This medication is used if you have had certain types of irregular heartbeat (paroxysmal or persistent atrial fibrillation) in the past but now have a normal heart rhythm. It helps you keep a normal heart rhythm and lowers your chance of having to go to the hospital for atrial fibrillation. Dronedarone is known as an antiarrhythmic drug.

This medication should not be used if you have permanent atrial fibrillation because of the increased risk of very serious side effects. See also Warning section.

Read the Medication Guide provided by your pharmacist before you start taking dronedarone and each time you get a refill. If you have any questions, ask your doctor or pharmacist.

Take this medication by mouth with food as directed by your doctor, usually twice daily (once with your morning meal and once with your evening meal).

Avoid eating grapefruit or drinking grapefruit juice while using this medication unless your doctor or pharmacist says you may do so safely. Grapefruit can increase the chance of side effects with this medicine. Ask your doctor or pharmacist for more details.

Take this medication regularly to get the most benefit from it. To help you remember, take it at the same times each day. Do not stop taking dronedarone without asking your doctor first. Keep taking this medication even if you feel well. Your doctor may direct you to also take another medication ("blood thinner"/anticoagulant) to lower the risk of getting serious blood clots. Follow your doctor's instructions carefully.

Get medical help right away if your heartbeat or pulse becomes fast or irregular.

See also Warning section.

Nausea or diarrhea may occur. If either of these effects lasts or gets worse, tell your doctor promptly.

Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor right away if you have any serious side effects, including:

• symptoms of liver disease (such as nausea/vomiting that doesn't stop, loss of appetite, stomach/abdominal pain, yellowing eyes/skin, dark urine)
• symptoms of lung problems (such as dry cough that doesn't go away, shortness of breath)
• signs of kidney problems (such as change in the amount of urine)

Get medical help right away if you have any very serious side effects, including:

• slow/fast/irregular heartbeat
• severe dizziness
• fainting

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including:

• rash
• itching/swelling (especially of the face/tongue/throat)
• severe dizziness
• trouble breathing

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

See also Warning section.

Before taking dronedarone, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of:

• liver disease
• certain types of irregular heartbeat (second- or third-degree atrioventricular block or sick sinus syndrome, unless you have a heart pacemaker)
• serious side effects (such as liver/lung disease) from taking the medication amiodarone

Dronedarone may cause a condition that affects the heart rhythm (QT prolongation). QT prolongation can rarely cause serious (rarely fatal) fast/irregular heartbeat and other symptoms (such as severe dizziness, fainting) that need medical attention right away.

The risk of QT prolongation may be increased if you have certain medical conditions or are taking other drugs that may cause QT prolongation. Before using dronedarone, tell your doctor or pharmacist of all the drugs you take and if you have any of the following conditions:

• certain heart problems (heart failure, slow heartbeat, QT prolongation in the EKG)
• family history of certain heart problems (QT prolongation in the EKG, sudden cardiac death)

Low levels of potassium or magnesium in the blood may also increase your risk of QT prolongation. This risk may increase if you use certain drugs (such as diuretics/"water pills") or if you have conditions such as severe sweating, diarrhea, or vomiting. Talk to your doctor about using dronedarone safely.

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

Older adults may be more sensitive to the side effects of this drug, especially QT prolongation (see above).

Tell your doctor if you are pregnant or plan to become pregnant. You should not become pregnant while using dronedarone. Dronedarone may harm an unborn baby. Your doctor should order a pregnancy test before you start this medication. Ask about reliable forms of birth control while using this medication and for 5 days after the last dose. If you become pregnant, talk to your doctor right away about the risks and benefits of this medication.

It is unknown if this medication passes into breast milk. Because of the possible risk to the infant, breastfeeding is not recommended while using this medication and for 5 days after the last dose. Consult your doctor before breastfeeding.

See also How to Use section.

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

A product that may interact with this drug is:

• fingolimod

Many drugs besides dronedarone may affect the heart rhythm (QT prolongation). Examples include amiodarone, disopyramide, dofetilide, flecainide, pimozide, procainamide, propafenone, quinidine, sotalol, among others.

Other medications can affect the removal of dronedarone from your body, which may affect how dronedarone works. Examples include azole antifungals (such as ketoconazole, itraconazole, voriconazole), cyclosporine, macrolide antibiotics (such as clarithromycin, erythromycin), nefazodone, HIV protease inhibitors (such as lopinavir), rifampin, ritonavir, St. John's wort, drugs used to treat seizures (such as carbamazepine, phenobarbital, phenytoin), telithromycin, among others.

Dronedarone can slow down the removal of other medications from your body, which may affect how they work. Examples of affected drugs include dabigatran, digoxin, domperidone, elacestrant, flibanserin, among others.

If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call 1-800-222-1222. Canada residents can call 1-844-764-7669.

Do not share this medication with others.

Lab and/or medical tests (such as EKG, kidney/liver function, blood mineral levels including potassium) should be done while you are taking this medication. Keep all medical and lab appointments. Consult your doctor for more details.

If you miss a dose, skip the missed dose and take your next dose at your regular scheduled time. Do not double the dose to catch up.

Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.

Your condition can cause complications in a medical emergency. For information about enrolling in MedicAlert, call 1-888-633-4298 (US) or 1-800-668-1507 (Canada).