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Centrally Acting Antiadrenergic Agents

        Health | Heart

Centrally acting antiadrenergic medicines can be used in a pill by themselves or in a combination pill with a diuretic.

Common Names of Centrally Acting Antiadrenergic Agents

The following table lists some of the common brand and generic names for centrally acting antiadrenergic agents.


brand generic
Aldomet methyldopa
Catapres (oral) clonidine HCl
Catapres-TTS (transdermal, which means a patch) clonidine HCl
Tenex guanfacine HCl
Wytensin guanabenz acetate

How Centrally Acting Antiadrenergic Agents Work

Your brain produces chemicals called neurotransmitters. 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. Centrally acting antiadrenergic medicines keep your brain from releasing catecholamines. When catecholamines are blocked, your heart beats more slowly and with less force. Your blood vessels also relax and widen so that blood flows through them more easily. Both of these actions lower blood pressure.

Precautions and Possible Side Effects

Precautions to take if you are on centrally acting antiadrenergic agents:

  • 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.
  • Keep all your follow-up appointments with your doctor. Your doctor will check to see how your medicine is working and will adjust it if needed.
Possible side effects of centrally acting antiadrenergic agents you may notice:
  • depression
  • dizziness
  • drowsiness
  • slow heartbeat
  • dry mouth
  • nausea
  • skin rash
  • sleep disturbances
Possible side effects of centrally acting antiadrenergic agents you may not notice:
  • liver problems
  • anemia or low blood count

Not everyone who takes centrally acting antiadrenergic medicines 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 Centrally Acting Antiadrenergic Agents

Before you take a centrally acting antiadrenergic agent, tell your doctor and 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 centrally acting antiadrenergic agent to prescribe that is the least likely to interact with your other treatments.


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