Beta-blockers

Published by Bupa’s Health Information Team, July 2011.

This factsheet is for people who are taking beta-blockers, or who would like information about them.

Beta-blockers (or beta-adrenoreceptor blocking drugs) are medicines that mainly work on the heart muscles where they act to reduce the amount of work the heart does. They are also used to reduce symptoms of anxiety and to help prevent migraines.

Why would I take beta-blockers?

Your GP may prescribe beta-blockers for you if you have:

• chest pain (angina)
• high blood pressure
• disturbance in the normal rhythm of your heart (arrhythmia)
• heart failure
• had a heart attack – to reduce your risk of having another one

Your GP may also suggest beta-blockers to:

• help prevent migraines
• slow down thyroid activity before a thyroid operation
• treat glaucoma (an eye condition caused by a build-up of pressure in the eye)

Beta-blockers are also used to relieve the symptoms of anxiety, such as palpitations and fast heart rate. However, they will not stop the feeling of anxiety itself.

How do beta-blockers work?

Beta-blockers prevent certain chemicals in your body, called noradrenaline and adrenaline, from acting on your blood vessels, heart muscle and other organs.

Noradrenaline and adrenaline cause your blood vessels to narrow and your heart to beat faster. By blocking their action, beta-blockers cause your blood vessels to widen, slow down your heart and reduce the force at which blood is pumped around your body. This results in a drop in blood pressure and less work for your heart.

Some beta-blockers only work on your heart, whereas others work on many different parts of your body.

How to take beta-blockers

Beta-blockers are only available on prescription from a doctor. The type of beta-blocker you're prescribed depends on why you need them. They come as:

• tablets or capsules
• syrup or solution
• injections
• eye drops (for glaucoma)

The effects of some beta-blockers don’t last very long, so if you need beta-blocker tablets to help control a long-term condition such as angina, you may need to take them once or twice a day.

Beta-blockers may be prescribed in combination with other medicines, such as calcium-channel blockers.

Don’t stop taking a beta-blocker suddenly because this may make your symptoms worse. If you need to stop taking them, your GP will tell you how to reduce your dose gradually.

Always ask your GP for advice and read the patient information leaflet that comes with your medicine.

Special care

Beta-blockers may affect other parts of your body, such as your lungs and muscles. For this reason, your GP may not prescribe you a beta-blocker, or will need to monitor you closely, if you have:

• asthma or other breathing problems
• severe heart failure
• severe narrowing of the arteries that carry blood to your arms and legs (peripheral arterial disease)
• low blood pressure
• a slow heart rate
• diabetes – because beta-blockers can hide the symptoms of low blood sugar levels, especially if you're already taking a diuretic

However, there are some circumstances in which beta-blockers can be given to people who have these conditions. Ask your GP for more information.

Side-effects of beta-blockers

Side-effects are the unwanted effects of taking a medicine. The side-effects you might have with your beta-blocker depend on which one you're taking. This section does not include every possible side-effect of beta-blockers. Please read the patient information leaflet that comes with your medicine for more information. Some common side-effects are:

• cold hands and feet
• tiredness
• headache
• dizziness
• sleep disturbance (nightmares)
• sexual problems (erectile dysfunction)

Other side-effects can include:

• wheezing
• indigestion
• visual disturbances
• skin rashes
• dry eyes

If you have side-effects, it’s important to talk to your GP or the healthcare professional who prescribed your medicine before you stop taking it.

Interactions of beta-blockers with other medicines

Check with your GP or pharmacist before you take any other medicines or herbal remedies at the same time as a beta-blocker.

You may find herbal remedies helpful but it’s important to remember that natural doesn’t mean harmless. Herbal remedies contain active ingredients and may interact with other medicines or cause side-effects. Don’t start taking any herbal remedies without speaking to your GP or pharmacist first.

Names of common beta-blockers

All medicines have a generic name. Many also have one or more brand name. Generic names are written in lower case, whereas brand names start with a capital letter.

For answers to frequently asked questions on this topic, see FAQs.

For sources and links to further information, see Resources.