Propafenone

Propafenone is a Class IC anti-arrhythmic that changes how your heart beats.

Propafenone is used in specific cases to stop serious heart rhythm problems.

Propafenone may also be used for reasons not mentioned in this medication guide.

Follow all instructions on your prescription label and read all medication guides or instruction sheets. Your doctor may change your dose from time to time. Use the medicine exactly as directed.

You can take propafenone with or without food.

You may experience very low blood pressure while taking this medicine. Call your doctor if you are sick with vomiting or diarrhea, extreme thirst, loss of appetite, or if you are sweating more than usual.

You may need regular blood tests. Your heart function may also need to be checked with an electrocardiograph or ECG (sometimes called an EKG), before and during treatment with propafenone.

Store at room temperature away from moisture, heat, and light. Keep the bottle tightly closed when not in use.

You should not use propafenone if you have heart failure, Brugada syndrome, sick sinus syndrome, AV block (without a pacemaker), severe low blood pressure, very slow heartbeats, a severe electrolyte imbalance, shortness of breath, or if you recently had a heart attack.

Propafenone may cause a new or worsening heartbeat pattern. Call your doctor right away if you have fast or pounding heartbeats, fluttering in your chest, shortness of breath, and sudden dizziness.

You should not use propafenone if you are allergic to it, or if you have:

• heart failure, or if you have recently had a heart attack;
• a genetic heart condition called Brugada syndrome;
• a serious heart condition such as "sick sinus syndrome" or "AV block" (unless you have a pacemaker);
• severe low blood pressure, or a history of slow heartbeats that have caused you to faint;
• a severe or uncontrolled electrolyte imbalance; or
• wheezing or shortness of breath.

Tell your doctor if you have ever had:

• a breathing disorder;
• liver or kidney disease;
• lupus;
• myasthenia gravis; or
• an abnormal blood test called Antinuclear Antibody Test or ANA.

Tell your doctor if you have a pacemaker or defibrillator. These devices may need to be re-programmed while you are taking propafenone.

Tell your doctor if you are pregnant or breastfeeding.

propafenone may affect fertility (ability to have children) in men. Talk with your doctor if you have concerns about this risk.

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

Propafenone may cause a new or worsening heartbeat pattern. Call your doctor right away if you have fast or pounding heartbeats, fluttering in your chest, shortness of breath, and sudden dizziness (like you might faint).

Also call your doctor right away if you have:

• shortness of breath (even with mild activity);
• swelling in your arms or legs;
• sudden weight gain; or
• fever, chills, sore throat.

Common side effects of propafenone may include:

• irregular heartbeats;
• nausea, vomiting, constipation;
• headache, dizziness, tiredness; or
• unusual or unpleasant taste in your mouth.

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 the FDA at 1-800-FDA-1088.

Take the medicine as soon as possible, but skip the missed dose if it is nearly time for your next dose. Do not take two doses at the same time.

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Grapefruit may interact with propafenone and cause unwanted side effects. Avoid using grapefruit products.

Sometimes, it is not safe to take certain medications together. Some drugs can change how your body processes other drugs you take, which may increase side effects or reduce how well the medications work.

Propafenone can cause a serious heart problem. Your risk may be higher if you also use certain other medicines for infections, asthma, heart problems, high blood pressure, depression, mental illness, cancer, malaria, or HIV.

Many drugs can affect propafenone. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed here. Tell your doctor about all your current medicines and any medicine you start or stop using.