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Beta-Adrenergic Blocking Agents, Also Called Beta-Blockers

        Health | Heart

Beta-blockers belong to a larger class of medicines called adrenergic inhibitors. They may be used in pills by themselves or in combination pills with diuretics.

When are beta-blockers prescribed?

These medicines may be used to treat certain types of heart problems and migraine headaches as well as high blood pressure. Beta-blockers reduce your risk for heart disease and peripheral vascular disease. They are also used to treat arrhythmias. They tend to be less expensive than other medicines.

Common Names of Beta-Blockers

The following table lists some common brand and generic names for beta-blockers.

brand generic
Betachron E-R propranolol HCl
Blocadren timolol maleate
Brevibloc esmolol HCl
Cartrol carteolol HCl
Corgard nadolol
Inderal propranolol HCl
Inderal LA propranolol HCl
Kerlone betaxolol HCl
Levatol penbutolol sulfate
Lopressor metoprolol tartrate
Sectral acebutolol HCI
Tenormin atenolol
Toprol-XL metoprolol succinate
Visken pindolol
Zebeta bisoprolol fumarate

How Beta-Blockers Work

Your brain produces chemicals called neurotransmitters. Certain neurotransmitters, called catecholamines, are normally released when you are under stress. These chemicals cause your heart to beat faster and with more force. They also cause your blood vessels to narrow. Both of these actions raise your blood pressure. Beta-blockers block catecholamines. The result is that your heart beats more slowly and with less force. Your blood vessels also relax and widen. And that means that blood flows through them more easily. Both of these actions lower blood pressure. The actions also allow the heart to get more blood and oxygen. This is why beta-blockers are helpful for people with coronary heart disease. People who have recently had a heart attack are also often given beta-blockers to help prevent further damage to the heart.

Precautions and Possible Side Effects

Precautions you should take if you are on beta-blockers:

  • Talk with your doctor if you experience faintness or dizziness. Blood pressure medicines can occasionally cause dizziness. This is most likely to happen when you change position suddenly. But this may also be caused by other physical or medical problems that have nothing to do with your medicines.
  • Do not stop taking this medicine suddenly unless your doctor tells you to stop. Stopping suddenly may bring on the chest pain known as angina. Or, it may worsen this type of chest pain.

Possible side effects of beta-blockers that you may notice:

  • bleeding or bruising
  • cold hands and feet
  • coughing at night
  • dizziness
  • decreased or slow heartbeat
  • inability to sleep, called insomnia
  • sexual difficulties
  • skin rash
  • sore throat
  • tiredness
  • wheezing or shortness of breath in people who have asthma
  • depression

Not everyone who takes beta-blockers will have these side effects. You should not be afraid to take your medicine because of the side effects listed. They are listed so that you can watch out for them and tell your doctor right away if you experience any of them.

Possible side effects of beta-blockers that you may not notice:

  • changes in the electrical system of the heart
  • changes in your white blood cell count
  • changes in your liver blood tests

Beta-blockers might hide the warning signs of low blood glucose. If you have diabetes, this can be dangerous. Discuss this with your doctor.

Possible Drug Interactions With Beta-Blockers

Before you take a beta-blocker, tell all your doctors and your pharmacist about all the medicines you take. Include medicines you take for your blood pressure as well as for any other problem. Tell them about everything you take and how much you take each day, including all of the following:

  • prescription medicines
  • over-the-counter medicines
  • herbs
  • vitamin and mineral supplements

It's best to keep an updated list of these and bring a copy to give to your doctor. That way you can add to it whenever you take something new or delete the types you no longer take. Make a copy for each of your doctors so that they can keep it in your file. This complete list helps your doctor be better prepared to prescribe a beta-blocker that is the least likely to interact with your other treatments.