Generic Name: propafenone (proe PAF e none)Brand Names: Rythmol, Rythmol SR
Propafenone is in a group of drugs called Class IC anti-arrhythmics. It affects the way your heart beats.
Propafenone is used in certain situations to prevent serious heart rhythm disorders.
Propafenone may also be used for other purposes not listed in this medication guide.What is the most important information I should know about Rythmol SR (propafenone)?You should not use this medication if you are allergic to propafenone, or if you have untreated or uncontrolled congestive heart failure, a heart condition called "sick sinus syndrome" or "AV block" (unless you have a pacemaker), slow heartbeats or severely low blood pressure, an electrolyte imbalance, or a breathing disorder such as asthma.
Before you take propafenone, tell your doctor if you have congestive heart failure, liver or kidney disease, lupus, arthritis, myasthenia gravis, or if you have had a heart attack within the past 2 years.You will need to receive your first few doses of propafenone in a hospital setting in case the medication causes serious side effects. Your heart rate will be constantly monitored using an electrocardiograph or ECG (sometimes called an EKG). This machine measures electrical activity of the heart. Call your doctor at once if you have a serious side effect such as weak pulse, slow breathing, feeling like you might pass out, feeling short of breath, swelling, rapid weight gain, pale skin, easy bruising or bleeding, unusual weakness, confusion, unusual thoughts or behavior, or seizure.What should I discuss with my healthcare provider before taking Rythmol SR (propafenone)?You should not use this medication if you are allergic to propafenone, or if you have:
untreated or uncontrolled congestive heart failure;
a heart condition called "sick sinus syndrome" or "AV block" (unless you have a pacemaker);
slow heartbeats or severely low blood pressure;
an electrolyte imbalance; or
a breathing disorder such as asthma.
If you have any of these other conditions, you may need a dose adjustment or special tests to safely take propafenone:
congestive heart failure;
myasthenia gravis; or
if you have had a heart attack within the past 2 years.
Take this medication exactly as prescribed by your doctor. Do not take it in larger amounts or for longer than recommended. Follow the directions on your prescription label.
Your doctor may occasionally change your dose to make sure you get the best results from this medication.
To be sure this medication is helping your condition, your blood may need to be tested on a regular basis. Do not miss any scheduled appointments.Store propafenone at room temperature away from moisture, heat, and light.
Take the missed dose as soon as you remember. If it is almost time for your next dose, wait until then to take the medicine and skip the missed dose. Do not take extra medicine to make up the missed dose.
Overdose symptoms may include drowsiness, slow heart rate, feeling like you might pass out, or seizure (convulsions).
Grapefruit and grapefruit juice may increase your blood levels of propafenone which could lead to unwanted side effects. Discuss the use of grapefruit products with your doctor. Do not increase or decrease the amount of grapefruit products in your diet without first talking to your doctor.
feeling short of breath, even with mild exertion;
swelling, rapid weight gain;
slow heart rate, weak pulse, fainting, slow breathing (breathing may stop);
pale skin, easy bruising or bleeding, unusual weakness;
confusion, unusual thoughts or behavior; or
Less serious side effects may include:
unusual or unpleasant taste in your mouth;
warmth, redness, or tingly feeling under your skin;
ringing in your ears;
unusual dreams; or
This is not a complete list of side effects and others may occur. Tell your doctor about any unusual or bothersome side effect. You may report side effects to FDA at 1-800-FDA-1088.
Many drugs can interact with propafenone. Below is just a partial list. Tell your doctor if you are using:
digoxin (digitalis, Lanoxin);
orlistat (alli, Xenical);
quinidine (Quinaglute, Quinidex, Quin-Release);
rifampin (Rifadin, Rifamate, Rimactane);
a blood thinner such as warfarin (Coumadin);
an antidepressant such as desipramine (Norpramin), fluoxetine (Prozac), imipramine (Tofranil), paroxetine (Paxil), sertraline (Zoloft), or venlafaxine (Effexor);
HIV or AIDS medication such as ritonavir (Norvir) or saquinavir (Invirase);
another heart rhythm medication such as amiodarone (Cordarone, Pacerone);
medicine to treat psychiatric disorders, such as haloperidol (Haldol); or
a beta-blocker such as atenolol (Tenormin), labetalol (Normodyne, Trandate), metoprolol (Lopressor, Toprol), propranolol (Inderal, InnoPran), sotalol (Betapace), timolol (Blocadren), and others.
This list is not complete and there may be other drugs that can interact with propafenone. Tell your doctor about all your prescription and over-the-counter medications, vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start a new medication without telling your doctor.