Examples
| Generic Name | Brand Name |
|---|
| amiodarone | Cordarone, Pacerone |
| disopyramide | Norpace |
| dofetilide | Tikosyn |
| flecainide | Tambocor |
| procainamide | |
| propafenone | Rythmol |
| quinidine | Quinaglute, Quinidex |
| sotalol | Betapace AF |
How It Works
Antiarrhythmic medicines help return the
heart to its
normal sinus rhythm, maintain the rhythm after it has
been achieved, and/or reduce the heart rate while you are in atrial
fibrillation. These medicines stabilize the heart muscle tissue.
Antiarrhythmics such as amiodarone or sotalol also slow the heart rate by
blocking impulses that pass through the
AV node in the heart.
Why It Is Used
Antiarrhythmic medicines are used to
convert
atrial fibrillation to a normal rhythm. These
medicines may be used before
electrical cardioversion and may help maintain a
normal heart rhythm after successful cardioversion. Ibutilide, another
antiarrhythmic, may improve chances of successful cardioversion when used
before cardioversion.
How Well It Works
Antiarrhythmic medicines can
maintain a normal rhythm in 35% to 75% of the people who use them.1
Side Effects
Antiarrhythmic medicines may increase
the risk of developing a more severe irregular heart rate problem (ventricular
tachycardia or ventricular fibrillation). Close monitoring while taking the
medicine is important. The risk of side effects is greater with more severe
underlying heart disease.
Side effects of antiarrhythmics
include:
- Slow
heartbeat.
- Palpitations.
- Fatigue.
- Headache.
- Dizziness.
- Nausea
or vomiting.
- Unusual taste in the mouth.
- Stomach
pain.
- Constipation or diarrhea.
- Difficulty
breathing.
- Rash.
- Vision problems.
- Urinary
retention in men.
- Arrhythmia.
Other, less common side effects include:
- Sensitivity to light
(photosensitivity).
- Thyroid disorders.
- Cirrhosis of the
liver.
- Peripheral neuropathies.
Rare side effects of amiodarone include:
- Scarring of the lungs (pulmonary
toxicity).
- A blue tinge to the skin.
- Vision
problems.
- Numbness.
- Tremor.
The U.S. Food and Drug Administration (FDA) has issued
warnings about amiodarone (Cordarone). People taking this medicine should be
aware that it may cause serious side effects that can lead to death, including
lung damage, liver damage, and more severe heartbeat problems. Amiodarone is
typically used for people who have severe symptoms when other medicines have
failed.
If you take amiodarone and simvastatin, which is a
cholesterol medicine, you may have a higher risk of a serious muscle problem
called
rhabdomyolysis. Simvastatin medicines include Zocor
and Vytorin.
Talk to your doctor if you have any side effects or
any concerns about taking amiodarone. People may be able to take amiodarone
safely when they are checked carefully by their doctors.
See Drug
Reference for a full list of side effects. (Drug Reference is not available in
all systems.)
What To Think About
Antiarrhythmics must be used
carefully to treat atrial fibrillation because they can cause severe irregular
heart rate problems and other serious side effects. They often are used for
people who have severe symptoms of atrial fibrillation or whose symptoms are
bothersome. Antiarrhythmics also are used after cardioversion to control heart
rhythm.
For some people, antiarrhythmic medicines may not be the
preferred treatment. In a study called the AFFIRM trial, medicines to slow the
heart rate, such as
beta-blockers,
calcium channel blockers, and digoxin, were found to
be preferable to antiarrhythmic medicines as a first-line treatment for certain
people with atrial fibrillation, specifically older people at risk for stroke
who did not have severe symptoms of atrial fibrillation.2
Taking medicines that only slow your heart rate
will leave you in atrial fibrillation. But most people tolerate an irregular
heart rhythm if the rate is kept between 60 and 100 beats per minute. Also, the
AFFIRM study found that antiarrhythmic medicines were expensive, often had side
effects, and frequently did not prevent atrial fibrillation from
recurring.2 So, treatment with a rate-control medicine
and an anticoagulant might be a good option for people who do not have atrial
fibrillation symptoms when their heart rate is controlled.
Amiodarone is an effective antiarrhythmic for treating atrial
fibrillation, but its use is limited by its potential severe side
effects.
Sotalol has both antiarrhythmic and beta-blocking
properties.
Because atrial fibrillation often returns, you may
also need to take
anticoagulant medicine (warfarin, such as
Coumadin).
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