Medically Reviewed by James Beckerman, MD, FACC on November 17, 2022

When and Why to Take Medicine for AFib

1/13

For many people with atrial fibrillation (AFib), medications are the best way to treat the condition. Drugs can prevent blood clots, reset your heart’s rhythm, control your heart rate, and lower your odds for a stroke. If you haven’t had untreated AFib for a long time, your doctor may be able to get your heart rate back to normal with these medicines.

Anticoagulant Blood Thinners

2/13

Because AFib makes your heartbeat irregular, blood can pool in your heart’s chambers. That means clots could form, which raises your odds of a stroke. Anticoagulants are drugs that help prevent clots. They keep your body from making proteins that play a role in how clots form. Your doctor will probably prescribe one to cut your stroke risk. Warfarin is a common choice. Others are dabigatran, rivaroxaban, edoxaban, and apixaban -- a group called DOACs.

Anticoagulants: Side Effects and Risks

3/13

These drugs work very well to prevent strokes. But they raise your chances for bleeding, which could be severe. If you take warfarin, you’ll need to have regular blood tests to make sure the dose you’re getting is right. You’ll also need to watch your diet carefully. DOACs don’t require a blood test. But if you have a mechanical heart valve, you can’t take them.

Antiplatelet Blood Thinners

4/13

These drugs, such as aspirin and clopidogrel, also can prevent blood clots in people with AFib. They may also bust up an existing clot. They do not work as well as anticoagulants. But your doctor may prescribe them if you can’t take those other blood thinners.

Antiplatelets: Side Effects and Risks

5/13

These blood thinners also can raise your risk of bleeding. If you notice blood in your stool, bleeding gums, heavy periods, weakness, or dizziness, let your doctor know right away. You can buy aspirin over the counter, but never take more than your doctor prescribes.

Beta-Blockers

6/13

These are medications that your doctor may prescribe to help you restore your heart rate -- the number of beats per minute -- to normal. They’re blood pressure medicines that can slow down your heart if it beats too fast.  Options include atenolol, bisoprolol, carvedilol, metoprolol, nadolol, propranolol, and timolol.

Beta-Blockers: Side Effects

7/13

Because they slow down your heart rate, beta-blockers may help you feel better overall. But they can cause side effects like low blood pressure, insomnia, cold hands or feet, asthma symptoms, or erection problems in men. They also may make you feel tired or depressed. Let your doctor know if you're pregnant or want to try to conceive while on beta-blockers.

Calcium Channel Blockers

8/13

These blood pressure drugs, such as diltiazem and verapamil, relax your blood vessels and keep your heart from working so hard. The muscle cells of the heart and arteries use calcium to create a stronger, harder contraction. Calcium channel blockers work by stopping the flow of calcium into those cells, which slows that speedy heart rate in AFib. They can control your irregular heartbeat, lower high blood pressure, and ease chest pain.

Calcium Channel Blockers: Side Effects

9/13

These drugs can cause constipation, dizziness, headaches, heart palpitations, or swollen ankles or feet. If you have low blood pressure or heart failure, calcium channel blockers may not be a good choice to treat your AFib.

Digoxin

10/13

This is a type of drug called a cardiac glycoside. It helps slow down your heart rate. AFib makes your heart fill with a different amount of blood each time it beats. That means your blood delivers an uneven amount of oxygen throughout your body. Digoxin improves how your heart fills with blood, which may ease AFib symptoms like feeling dizzy or lightheaded. It can also improve blood circulation and lower swelling in your ankles or hands.

Digoxin: Side Effects

11/13

The drug can make your heartbeat stronger and steadier. But it does have many possible side effects, such as nausea, vomiting, fainting, and heart palpitations. Your doctor will probably try beta-blockers or calcium channel blockers to control your heart rate before they prescribe digoxin. You may also take it along with those other drugs.

Antiarrhythmics

12/13

After drugs slow your heart rate, your doctor may prescribe others to steady its rhythm. Your heart uses electric signals to control its pattern of beats. One type of antiarrhythmic, sodium channel blockers, such as flecainide, propafenone, and quinidine, slow down how your heart conducts electricity. Another type, potassium channel blockers, such as amiodarone, sotalol, and dofetilide, slow down the electric signals that lead to AFib.

Antiarrhythmics: Side Effects

13/13

These drugs don’t work well for everyone, and they may cause some serious side effects. They could cause new heart rhythm problems or make the one you have worse. Those risks mean that your doctor may only prescribe them for severe AFib or if other drugs haven’t helped. Your doctor will want to watch you closely while you take these drugs.