Examples

How It Works

Beta-blockers relax blood vessels. It is not clear how they work to prevent migraines.

Why It Is Used

Beta-blockers are preventive medicines that are used to prevent migraine headaches in some people who get them regularly.

How Well It Works

These medicines can reduce the number of migraines you get each month by more than half. This happened in about 50 out of 100 people who took one of these medicines to prevent migraines.¹

Side Effects

All medicines have side effects. But many people don't feel the side effects, or they are able to deal with them. Ask your pharmacist about the side effects of each medicine you take. Side effects are also listed in the information that comes with your medicine.

Here are some important things to think about:

• Usually the benefits of the medicine are more important than any minor side effects.
• Side effects may go away after you take the medicine for a while.
• If side effects still bother you and you wonder if you should keep taking the medicine, call your doctor. He or she may be able to lower your dose or change your medicine. Do not suddenly quit taking your medicine unless your doctor tells you to.

Call 911 or other emergency services right away if you have:

• Trouble breathing.
• Hives.
• Swelling of your face, lips, tongue, or throat.
• Fainting or severe dizziness.

Call your doctor right away if you have:

• A very slow heart rate (less than 50 beats per minute).
• Swelling in your legs or feet.
• Shortness of breath or wheezing, especially if you have asthma.
• Cold hands and feet.

Common side effects of this medicine include:

• Dizziness or lightheadedness.
• Feeling tired.
• Trouble sleeping.

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

What To Think About

Check your pulse. Your doctor may ask you to take your pulse regularly to make sure your heart rate is not too slow. To learn how to take your pulse, see the topic Taking a Pulse (Heart Rate).

Diabetes. If you have diabetes, beta-blockers may cause higher blood sugar levels. Watch closely for symptoms of low blood sugar, because beta-blockers can hide your symptoms.

Grapefruit juice. Grapefruit juice may affect how beta-blockers work. Ask your doctor if you need to make any changes to avoid problems. For more information, see Grapefruit Juice and Medicines.