Propafenone hydrochloride (By mouth)


Propafenone Hydrochloride (proe-PA-fen-one hye-droe-KLOR-ide)
Treats an irregular heartbeat (arrhythmia). This medicine is a class 1C antiarrhythmic.

Brand Name(s)

There may be other brand names for this medicine.

Rythmol, Rythmol SR

When This Medicine Should Not Be Used

You should not use this medicine if you have ever had an allergic reaction to propafenone, or if you have certain heart problems. Your doctor will determine if this medicine is right for you.

How to Use This Medicine

Tablet, Long Acting Capsule
  • Your doctor will tell you how much of this medicine to use and how often. Do not use more medicine or use it more often than your doctor tells you to.
  • Take this medicine exactly as your doctor ordered, even if you feel fine.
  • You may take this medicine with or without food.Swallow the extended-release capsule whole. Do not crush, break, or chew it.
  • You may need to carry identification stating that you are using propafenone. Ask your doctor about this.
If a dose is missed:
  • Take the missed dose as soon as you can, unless you are more than 4 hours late.
  • If you are more than 4 hours late, skip the missed dose and take your medicine at your usual time.
  • You should not use two doses at the same time.

How to Store and Dispose of This Medicine

  • Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.
  • Ask your pharmacist, doctor, or health caregiver about the best way to dispose of any outdated medicine or medicine no longer needed.
  • Keep all medicine away from children and never share your medicine with anyone.

Drugs and Foods to Avoid

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.
  • There are many other drugs that can interact with propafenone. Make sure your doctor knows about all other medicines you are using, especially lidocaine, ritonavir (Norvir®), quinidine (Cardioquin®, Quinaglute®), or other heart medicine such as amiodarone, Lanoxin®, Cordarone®, or Cardizem®. Tell your doctor if you use a blood thinner such as Coumadin®, or a beta-blocker such as atenolol, metoprolol, propranolol, or Lopressor®, or Tenormin®.
  • Make sure your doctor knows if you use arsenic trioxide (Trisenox®), cisapride (Propulsid®), dofetilide (Tikosyn®), or Tagamet®. Tell your doctor if you use certain antibiotics such as erythromycin, levofloxacin, Avelox®, or Zagam®. Your doctor should know if you also use medicine for depression or mental illness, such as Effexor®, Elavil®, Haldol®, Norpramin®, Paxil®, Prozac®, Seroquel®, Compazine®, Geodon®, Mellaril®, Tofranil®, or Zoloft®.

Warnings While Using This Medicine

  • Make sure your doctor knows if you are pregnant or breast feeding. Tell your doctor if you have kidney disease, liver disease, asthma, bronchitis, or emphysema. Tell your doctor if you have congestive heart failure, you have a pacemaker, you have had a recent heart attack, or you have a family history of "Long-QT" syndrome.
  • Do not stop using this medicine suddenly without asking your doctor. You may need to slowly decrease your dose before stopping it completely.
  • This medicine may make you dizzy or drowsy. Avoid driving, using machines, or doing anything else that could be dangerous if you are not alert.

Possible Side Effects While Using This Medicine

Call your doctor right away if you notice any of these side effects:
  • Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing.
  • Blurred vision.
  • Chest pain, or worsening of heart rhythm problem.
  • Fast or pounding heartbeat.
  • Fever, chills, cough, sore throat, and body aches.
  • Lightheadedness or fainting.
  • Shortness of breath with cold sweat, and bluish-colored skin.
  • Swelling in your hands, ankles, or feet.
If you notice these less serious side effects, talk with your doctor:
  • Anxiety, dizziness, or hot flashes
  • Dry mouth or metallic or bitter taste.
  • Headache
  • Nausea, vomiting, constipation, or diarrhea.
  • Runny or stuffy nose.
  • Trembling or shaking

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088
Review Date: 2011-02-04 Reviewed By: Keywords: ,
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