What is a beta-blocker?
A beta-blocker is a medicine that is often used to treat high blood pressure and heart problems. Some examples of beta-blockers are atenolol, metoprolol and propranolol. This kind of medicine blocks the harmful effects of stress hormones on your heart. It also slows your heart rate. Beta-blockers can also be used to prevent migraine headaches and in eye-drops to treat glaucoma.
What kinds of heart problems are treated with a beta-blocker?
A beta-blocker is often used to treat high blood pressure or an irregular heart beat. This medicine can also be used to treat congestive heart failure, but some people who have severe heart failure may not be able to take a beta-blocker. A beta-blocker reduces the risk of another heart attack for people who have already had one.
What are some of the possible side effects of beta-blockers?
Most people who take beta-blockers do well and have no side effects. But because beta-blockers slow your heart, they may make you feel tired. You also may notice that you can't exercise as hard as you used to. For example, you may get out of breath when you take a walk or climb stairs. Some people can have a loss of sex drive and some men can have trouble with erections when they take beta-blockers. Talk to your doctor if you have these problems after you start taking a beta-blocker.
The beta-blocker may make you feel a little dizzy or lightheaded. Because this might happen to you, you shouldn't drive a car or operate dangerous machines until you know if your beta-blocker is going to make you feel dizzy. The dizziness usually goes away after you have been taking the medicine for a few days. If you keep feeling dizzy or lightheaded after a few days, tell your doctor.
Call your doctor right away if you have trouble breathing when you're taking a beta-blocker. You should also call your doctor if you gain weight for an unknown reason. Tell your doctor if you have fluid retention (if your hands, feet or legs start swelling). Call your doctor right away if you have chest pain or a very slow heartbeat (less than 50 heartbeats per minute).
Can I take a beta-blocker if I have diabetes?
Yes, you can take a beta-blocker if you have diabetes. But a beta-blocker may hide some of the warning signs of low blood sugar. For example, when you take a beta-blocker, your heart rate may not increase as it normally would in response to a low blood sugar level. You will need to check your blood sugar levels carefully after you start taking a beta-blocker. If you have low blood sugar often, your doctor may want to change the dosages of your diabetes medicine.
Can I take a beta-blocker if I have asthma or chronic lung disease?
Beta-blockers can be a problem for many people who have asthma. A beta-blocker can cause asthma attacks. If there is an important reason to try a beta blocker, your doctor will need to help you monitor your asthma very carefully.
Sometimes people who have a chronic lung disease such as emphysema or bronchitis can take beta-blockers. If you have lung disease and are taking a beta-blocker, call your doctor right away if you start having breathing problems.
What about other medicines?
Taking other medicines--even medicines that don't require a prescription--while you're taking a beta-blocker can cause serious problems. Tell your doctor about any other medicines that you take, and check with him or her before starting any new medications.
What is the best way to take beta-blockers?
You should take your beta-blocker exactly as your doctor tells you. Beta-blockers are usually taken once or twice a day. Try to take the medicine at the same time every day. Do not stop taking your beta-blocker without talking to your doctor first.
If you forget to take a dose and it has been a few hours or less since you missed the dose, take your beta-blocker as soon as you remember. But if it has been 4 to 6 hours or longer since you missed the dose, don't take the dose you missed. Instead, wait and take the next regular dose. Never take a double dose to catch up.
Optimizing Beta-Blocker Use After Myocardial Infarction by PA Howard, PHARM.D., and EF Ellerbeck, M.D., M.P.H. (American Family Physician October 15, 2000, http://www.aafp.org/afp/20001015/1853.html)
Written by familydoctor.org editorial staff