Alpha-beta adrenergic blockers combine the effects of the alpha blocker medicines and beta-blocker medicines.

Common Names of Alpha-beta Blockers

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

brand generic
Coreg carvedilol
Normodyne labetalol HCl
Trandate labetalol HCl

How Alpha-beta Blockers Work

Alpha-beta blockers belong to a larger class of medicines called adrenergic inhibitors. They combine the effects of two types of medicines. They behave like alpha blocker medicines when they affect special receptor cells in the smooth muscles of your blood vessels. This action stops your cells from receiving chemicals called catecholamines. These chemicals narrow your arteries. This makes your blood pressure go up. When these chemicals are blocked, your blood vessels can relax. This in turn allows your blood to flow more easily, resulting in lower blood pressure.

These medicines act like beta-blockers when they block these same catecholamines in your brain, heart, and blood vessels. The result is that your heart beats more slowly and with less force. Plus, your blood vessels relax and widen so that blood flows through them more easily. Both of these actions make your blood pressure go down.

Precautions and Possible Side Effects

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

  • Talk with your doctor if you experience faintness or dizziness when you are taking alpha-beta blockers. Blood pressure medicines can occasionally cause dizziness. This is most likely 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. It can also make chest pain worse. Stopping suddenly may even cause a heart attack.

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

  • dizziness or faintness
  • depression
  • diarrhea
  • dry eyes
  • slow heart rate
  • scalp tingling
  • sexual problems
  • skin rash
  • swelling of feet and legs
  • tiredness
  • wheezing or shortness of breath in people who have asthma

Possible side effects of alpha-beta blockers that you may not notice: Some people may have problems with the electrical system of their heart. Not everyone who takes an alpha-beta adrenergic blocker 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 Drug Interactions With Alpha-beta Blockers

Before you take an alpha-beta blocker, tell all of 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 an alpha-beta adrenergic blocker that is the least likely to interact with your other treatments.