Examples

Generic Name	Brand Name
atropine
digoxin	Lanoxin
phenytoin	Dilantin
propranolol	Inderal
quinidine

How It Works

Antiarrhythmic medicines act on the electrical system of the heart. They block some of the extra electrical activity in the cells of the heart. This makes the heart beat regularly.

Why It Is Used

Antiarrhythmic medicines are used to treat and prevent irregular heartbeats.

How Well It Works

Antiarrhythmic medicines help control irregular heartbeats; they do not treat the congenital heart defect itself.

Side Effects

The most common side effects of antiarrhythmic medicines are:

• Nausea and vomiting.
• Poor appetite.
• Low blood pressure (seen as dizziness, lightheadedness, and weakness).

See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)

What To Think About

Do not give any two medicines at the same time if both have a side effect of lowering blood pressure. Space them out so that 1 to 2 hours go by before giving the next medicine.

Doses of some antiarrhythmic medicines are given around the clock, even during the night. Blood levels of these medicines must remain constant in order to control irregular heartbeats.

If your child continues to have irregular heartbeats (feels like the heart is beating funny or very fast) while on antiarrhythmic medicine, talk to his or her doctor.

Do not stop giving antiarrhythmic medicine without the advice of your child's doctor. It is dangerous to stop some of these medicines suddenly.

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