Why do I need to take a beta-blocker?
Beta-blockers are used to treat high blood pressure (hypertension), congestive heart failure (CHF), abnormal heart rhythms (arrhythmias), and chest pain (angina). Beta-blockers are sometimes used in heart attack patients to prevent future heart attacks.
How do beta-blockers work?
- Beta-blockers "block" the effects of adrenaline on your body's beta receptors. This slows the nerve impulses that travel through the heart. As a result, your heart does not have to work as hard because it needs less blood and oxygen. Beta-blockers also block the impulses that can cause an arrhythmia.
- Your body has 2 main beta receptors: beta 1 and beta 2.
- Some beta-blockers are selective, which means that they block beta 1 receptors more than they block beta 2 receptors. Beta 1 receptors are responsible for heart rate and the strength of your heartbeat.
- Nonselective beta-blockers block both beta 1 and beta 2 receptors. Beta 2 receptors are responsible for the function of your smooth muscles (muscles that control body functions but that you do not have control over).
How much do I take?
There are many different kinds of beta-blockers. The amount of medicine that you need to take may vary. Talk to your doctor or pharmacist for more information about how and when to take this medicine.
What if I am taking other medicines?
Other medicines that you may be taking can increase or decrease the effect of beta-blockers. These effects are called an interaction. Be sure to tell your doctor about every medicine and vitamin or herbal supplement that you are taking, so he or she can make you aware of any interactions.
The following are categories of medicines that can increase or decrease the effects of beta-blockers. Because there are so many kinds of medicines within each category, not every type of medicine is listed by name. Tell your doctor about every medicine that you are taking, even if it is not listed below.
- Other medicines used to treat high blood pressure. These other medicines may increase the effect of beta-blockers.
- Certain anti-depressants.
- Allergy shots.
- Medicines to treat diabetes, including oral medicines (pills that you swallow) and insulin.
- Medicines to treat asthma, chronic bronchitis, and emphysema.
While on beta-blockers, you should also avoid eating or drinking products that have caffeine or taking over-the-counter cough and cold medicines, antihistamines, and antacids that contain aluminum. You should also avoid drinking alcohol, because it can decrease the effects of beta-blockers.
What else should I tell my doctor?
Talk to your doctor about your medical history before you start taking beta-blockers. The risks of taking the medicine need to be weighed against its benefits. Here are some things to consider if you and your doctor are deciding whether you should take a beta-blocker.
- You have allergies to foods or dyes. Beta-blockers may make your allergic reactions worse.
- You are thinking of becoming pregnant, you are pregnant, or you are breast-feeding your baby.
- You are over 60. Younger people tend to have fewer problems while taking beta-blockers.
- You have heart disease or poor circulation to your hands or feet.
- You have a slow heart rate (bradycardia) or heart block.
- You have asthma. Beta-blockers may make your condition worse.
- You have hay fever symptoms, chronic bronchitis, or emphysema.
- You have diabetes or hypoglycemia. Beta-blockers may hide the symptoms of low blood sugar.
- You have an overactive thyroid.
- You have kidney or liver disease.
What are the side effects?
Sometimes a medicine causes unwanted effects. These are called side effects. Not all of the side effects for beta-blockers are listed here. If you feel these or any other effects, you should check with your doctor.
Common side effects:
- Drowsiness or fatigue.
- Cold hands and feet.
- Weakness or dizziness.
- Dry mouth, eyes, and skin.
Less common side effects:
- Wheezing, trouble breathing, or shortness of breath.
- Slow heartbeat.
- Trouble sleeping or vivid dreams while asleep.
- Swelling of the hands and feet.
Rare side effects:
- Abdominal cramps.
- Throwing up.
- Back or joint pain.
- Skin rash.
- Sore throat.
- Memory loss, confusion, or hallucinations.
Again, tell your doctor right away if you have any of these side effects. Do not stop taking your medicine unless your doctor tells you to. If you stop taking your medicine without checking with your doctor, it can make your condition worse.
Updated October 2013