When you have atrial fibrillation, the goal is to get your heart rate under control and try to bring your heart back to rhythm. In addition, your doctor will want to help you prevent blood clots that can lead to a stroke. For many people with AFib, medicine is the best treatment option.
Learn which medicines your doctor could prescribe to treat your AFib. You'll get the most benefit from these medications if you take them just as your doctor and pharmacist tell you.
Atrial Fibrillation Medications
With AFib, abnormal electrical signals make your heart quiver or flutter. It can also beat too fast. This sensation is sometimes called palpitations.
AFib prevents blood from flowing normally from your heart's upper chambers (called the atria) to the lower ones (the ventricles). Blood can pool in the atria and form clumps called clots. If one travels to your brain, it could cause a stroke.
Medicines do a few different things. They can:
- Prevent blood clots. These types of medications lower your chances of having a stroke.
- Slow your heart rate. Some medications lower the number of times your ventricles contract each minute. This slowed rhythm gives them enough time to fill with blood before pumping it out to your body.
- Control your heart rhythm. Other medicines help your atria and ventricles work together to pump blood better.
Blood Thinners to Prevent Clots and Stroke
Blood-thinning medicines help prevent blood clots. Blood clots can move to other parts of your body and cause serious medical problems, such as a stroke. Blood thinners won’t dissolve a blood clot. However, over time, the blood clot may dissolve on its own. Blood thinners may also prevent other clots from forming or growing. They can lower your chances of a stroke by 50% to 70%.
Blood thinners are not the same as clot busters, which you may get in the hospital when you have a stroke or heart attack. Clot busters, also called fibrinolytics or thrombolytics, work by dissolving existing blood clots.
There are other blood thinners you may be given in the hospital, or even at home for a short time. These are common blood thinners you may be given either by vein (IV) or just under the skin in the hospital:
- Dalteparin (Fragmin)
- Enoxaparin sodium (Lovenox)
Other blood thinners come as pills you take daily. Some examples of these drugs are:
- Apixaban (Eliquis)
- Betrixaban (Bevyxxa)
- Clopidogrel (Plavix)
- Dabigatran (Pradaxa)
- Edoxaban (Lixiana, Savaysa)
- Rivaroxaban (Xarelto)
- Warfarin (Coumadin, Jantoven)
All of these medicines can raise your chances of bleeding. Be very careful when you play sports or do activities that could cause you to injure yourself and bleed.
Blood Thinner Side Effects
Blood thinners have a number of possible side effects. They can make you more likely to bruise or bleed too much. If you take warfarin, for example, you'll see your doctor for a blood test every month to make sure it’s working and you're on the right dose.
Call your doctor right away if:
- You have any unusual bleeding or bruising.
- You have an accident of any kind.
- You often find bruises or blood blisters.
- You feel sick, weak, faint, or dizzy.
- You think you’re pregnant.
- You notice red, dark brown, or black stools or urine.
- Your periods get heavier.
- Your gums bleed.
- You have a severe headache or stomachache that won't go away.
- You look pale (symptoms of anemia).
- You cough or vomit blood (which may look like coffee grounds).
- You have a fever or illness that gets worse.
- You have unusual pain or swelling.
- You have difficulty breathing.
- Take your dose as instructed. Try to take it at the same time each day, like early in the evening (such as between 5 and 6 p.m.). You can take warfarin with or without food.
- If you forget a dose, don’t take an extra one to make it up. Ask your doctor what to do.
- Ask your doctor about differences if you switch from one type of blood thinner to another.
- Tell other doctors and your dentist if you’re taking one of these mediations if you plan to have a procedure that could cause bleeding.
- If you’re taking warfarin, tell any doctor who wants to give you a new medication. Some drugs and vitamins change the way it works in your body.
Beta-Blockers to Slow Your Heart Rate
One group of AFib medications alters the electrical signals in your heart to slow your heart rate. These medicines don't necessarily fix the abnormal heart rhythm, but they can help you feel better.
Beta-blockers are a type of blood pressure medicine. Some of them are:
- Atenolol (Tenormin)
- Bisoprolol (Zebeta, Ziac)
- Carvedilol (Coreg)
- Metoprolol (Lopressor, Toprol)
- Propranolol (Inderal, Innopran)
- Timolol (Blocadren, Istalol)
Side effects of beta-blockers can include:
- Feeling tired
- Cold hands and feet
- Weakness and dizziness
- Dry mouth, eyes, and skin
Precautions: Beta-blockers don’t work for everyone:
- Let your doctor know if you have asthma. They can cause severe asthma attacks.
- If you have diabetes, be aware they could block signs of low blood sugar, like a rapid heartbeat. Check your blood sugar often.
- They can raise your triglycerides and lower your good cholesterol, but these are short-term changes.
- Don’t suddenly stop taking a beta-blocker -- you could raise your odds of having a heart attack or other problems.
Calcium Channel Blockers to Slow Your Heart Rate
These are another type of blood pressure medicine. They relax blood vessels in your heart and slow your heart rate. Examples are:
- Diltiazem (Cardizem, Dilacor)
- Verapamil (Calan, Calan SR, Covera-HS, Isoptin SR, Verelan)
Some of the possible side effects of calcium channel blockers:
- Feeling tired
- Red skin
- Swelling of the belly, ankles, or feet
Precautions: Skip grapefruits and grapefruit juice if you’re taking calcium channel blockers. They can change the way these medications work.
Digoxin (Digox, Lanoxin) to Control Heart Rate
This medication strengthens the heart muscle's contractions and works on your heart's electrical system to slow the rate that signals move from the atria to the ventricles. Two common brands are Lanoxicaps and Lanoxin. Digoxin belongs to the digitalis class of medications.
You usually take this medication once daily. Try to take it at the same time every day. Follow the label directions on how often to take it. The time between doses and how long you take it will depend on your condition.
While taking digoxin, your doctor may tell you to check your pulse every day. They’ll tell you how fast your pulse should be. If it’s slower than that, talk to your doctor about taking digoxin that day.
Keep all your appointments with your medical team so they can keep track of how you react to the drug.
Digoxin may cause drowsiness. Don’t drive a car or use machinery until you discover how this medicine affects you.
If you have any of these side effects, call your doctor right away:
- Nausea and vomiting
- Stomach pain
- Appetite loss
- Slow or fast heartbeat
- Changes in vision, such as:
- Flashes or flickering of light
- Sensitivity to light
- Seeing things larger or smaller than they are
- Color changes (especially a yellow or green tint to your vision)
- Halos or borders on objects
These could mean your dose needs to be changed. Once you and your doctor have found the correct dose, you usually won’t have side effects as long as you take digoxin exactly as prescribed.
Channel Blockers to Control Heart Rhythm
If you aren't bothered by symptoms, your doctor may decide that correcting your heart's rhythm may not be worth the side effects.
But some people with AFib do struggle daily with fatigue, shortness of breath, and dizziness. If you do, your doctor may recommend an anti-arrhythmic medication to steady your heartbeat and help ease those symptoms. These medications control your heart rhythm by slowing the electrical signals through your heart. This type of treatment is called cardioversion with drugs, or sometimes chemical cardioversion.
Your doctor might recommend one of these medicines if rate control drugs alone haven't helped you. Heart rhythm medications work best if you just recently started having AFib. Most of the common anti-arrhythmic drugs work between 45% and 55% of the time.
There are two main types of channel blockers:
Sodium Channel Blockers
These drugs slow your heart's ability to conduct electricity. Some examples include:
- Flecainide (Tambocor)
- Procainamide (Procanbid)
- Propafenone (Rythmol)
Because these drugs slow down how fast electrical signals can travel in the heart muscle, people with coronary disease or any kind of heart failure can't use them.
Potassium Channel Blockers
Potassium channel blockers slow the electrical signals in the heart that cause AFib. They include:
- Dofetilide (Tikosyn)
- Sotalol (Betapace, Sorine, Sotylize)
These drugs affect the kidneys, which means you can't take them if you have kidney problems. And while it may help fix the rhythm in the top part of your heart, dofetilide might also cause life-threatening abnormal heartbeats in the bottom part of your heart, too. You'll start taking it in the hospital. That way, doctors and nurses can watch you carefully during the first few days, when most of these complications happen.
Side effects from these medications can range from blurred vision and dry mouth to a slowed heart rhythm. You might need to take a blood-thinning medicine for a few weeks before you start on one of these drugs to prevent a clot.
Amiodarone (Cordarone, Nexterone, Pacerone) is both a sodium channel blocker and a potassium channel blocker. It's by far the most effective anti-arrhythmic drug available, possibly as much as 75%.
Amiodarone Side Effects
Because amidarone lingers in many parts of the body for a long time, it can have many side effects. Get medical right away if you have:
- Low-grade fever
- Problems with walking
- Uncontrolled body movements, including shaky hands
- Numbness in your fingers or toes
- Sun sensitivity
- Pain when you breathe
Doctors won't usually prescribe amiodarone if you're young and likely to be treated for a long time. If you're on it, you'll have to have regular tests to check how well your liver, lungs, and thyroid are working.
A somewhat controversial newer drug called dronedarone (Multaq) was designed to be like amiodarone without the side effects. It does have fewer side effects, but clinical trials showed that it didn't keep people in sinus rhythm very well. It may not prevent AFib, but it might prevent some of the symptoms of AFib, perhaps by blunting fast heart rates.
In the United States, dronedarone is only approved for cutting down on hospitalization for people who have non-permanent (paroxsysmal or persistent) AFib.
Dronedarone Side Effects
In January 2011, the FDA reported that two people needed a transplant because of liver failure tied to dronedarone, an effect that didn't show up in clinical trials. A clinical trial of the drug was halted in July 2011 when people with permanent AFib showed twice the risk of death, stroke, and having to go to the hospital for heart failure. And in 2013, the FDA reported it can cause shortness of breath or a cough related to lung damage. While side effects aren't common with dronedarone, get medical help right away if you have these effects or any of the following:
- Chest discomfort or pain
- Slow or irregular heartbeat
- Dizziness or fainting
- Shortness of breath
- Extreme tiredness
Medicines are one option for treating AFib. If they don't work or you can't live with the side effects, you do have other choices, including surgery. Discuss all of your options with your doctor.