MedlinePlus Drug Information: Guanabenz

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Other drug names:	A-Am An-Az B C-Ch Ci-Cz D-Dh Di-Dz E F G H I-J K-L M-Mh Mi-Mz N-Nh Ni-Nz O P-Pl Pm-Pz Q-R S-Sn So-Sz T-To Tp-Tz U-V W-Z 0-9

Guanabenz

(gwahn' a benz)

Brand name(s): Wytensin

Contents of this page:
Why is this medication prescribed? How should this medicine be used? What special precautions should I follow? What special dietary instructions should I follow? What should I do if I forget a dose?	What side effects can this medication cause? What storage conditions are needed for this medicine? In case of emergency/overdose What other information should I know?

Why is this medication prescribed?

Guanabenz is used to treat high blood pressure. It works by decreasing your heart rate and relaxing the blood vessels so that blood can flow more easily through the body.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

How should this medicine be used?

Guanabenz comes as a tablet to take by mouth. It usually is taken twice a day at evenly spaced intervals. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take guanabenz exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Guanabenz controls high blood pressure but does not cure it. Continue to take guanabenz even if you feel well. Do not stop taking guanabenz without talking to your doctor.

Abruptly stopping guanabenz may increase blood pressure and cause unwanted side effects.

What special precautions should I follow?

Before taking guanabenz,

tell your doctor and pharmacist if you are allergic to guanabenz or any other drugs.
tell your doctor and pharmacist what prescription and nonprescription medications you are taking, especially other medications for high blood pressure, amitriptyline (Elavil), clomipramine (Anafranil), desipramine (Norpramin), doxepin (Adepin, Sinequan), imipramine (Tofranil), nortriptyline (Aventyl, Pamelor), protriptyline (Vivactil), sleeping pills, trimipramine (Surmontil), and vitamins.
tell your doctor if you have or have ever had coronary artery disease, kidney or liver disease, or a heart attack.
tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking guanabenz, call your doctor.
if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking guanabenz.
you should know that this drug may make you drowsy or dizzy. Do not drive a car or operate machinery until you know how this drug affects you.
ask your doctor about the safe use of alcohol while you are using guanabenz. Alcohol can make the side effects from guanabenz worse.

What special dietary instructions should I follow?

Your doctor may prescribe a low-salt or low-sodium diet. Follow these directions carefully.

What should I do if I forget a dose?

Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

What side effects can this medication cause?

Although side effects from guanabenz are not common, they can occur. Tell your doctor if any of these symptoms are severe or do not go away:

dry mouth
drowsiness
dizziness
weakness
headache
decreased sexual ability
upset stomach

If you experience any of the following symptoms, call your doctor immediately:

fainting
increased or decreased heartbeat
irregular heartbeat
swollen ankles or feet

What storage conditions are needed for this medicine?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store at room temperature and away from excess heat and moisture (not in the bathroom). Throw away any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.

In case of emergency/overdose

In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.

What other information should I know?

Keep all appointments with your doctor and the laboratory. Your blood pressure should be checked regularly to determine your response to guanabenz.

Your doctor may ask you to check your pulse (heart rate) daily and will tell you how rapid it should be. Ask your doctor or pharmacist to teach you how to take your pulse. If your pulse is slower or faster than it should be, call your doctor before taking the drug that day.

To avoid dizziness or faintness, get up slowly from a sitting or lying position. If you feel dizzy or faint at any time, you should lie or sit down.

To relieve dry mouth caused by guanabenz, chew gum or suck sugarless hard candy.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

Last Revised - 01/01/2003

American Society of Health-System Pharmacists, Inc. Disclaimer