Guanabenz

Generic Name: guanabenz (GWAN a benz)

Brand Names: Wytensin

What is guanabenz?

Guanabenz lowers blood pressure by decreasing the levels of certain chemicals in the blood. This allows the blood vessels (veins and arteries) to relax (widen).

Guanabenz is used to treat hypertension (high blood pressure).

Guanabenz may also be used for purposes other than those listed in this medication guide.

What is the most important information I should know about guanabenz?

Do not stop taking this medication without first talking to your doctor. Stopping suddenly may make your condition worse. This medication may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.

Avoid getting up too fast from a sitting or lying position, or you may feel dizzy. Get up slowly and steady yourself to prevent a fall.

Keep using this medicine as directed, even if you feel well. High blood pressure often has no symptoms. You may need to use blood pressure medication for the rest of your life.

What should I discuss with my healthcare provider before taking guanabenz?

You should not use guanabenz if you are allergic to it.

To make sure you can safely take guanabenz, tell your doctor if you have any of these other conditions:

• liver disease (especially cirrhosis);


• kidney disease, or if you are on dialysis;


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  heart disease; or

  
  


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  a recent history of heart attack or stroke.

  
  

FDA pregnancy category C. It is not known whether guanabenz will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant while using this medication. It is not known whether guanabenz passes into breast milk or if it could harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.

How should I take guanabenz?

Take exactly as prescribed by your doctor. Do not take in larger or smaller amounts or for longer than recommended. Follow the directions on your prescription label.

Guanabenz is usually taken 2 times each day. Follow your doctor's instructions.

Your blood pressure will need to be checked often. Visit your doctor regularly.

Keep using this medicine as directed, even if you feel well. High blood pressure often has no symptoms. You may need to use blood pressure medication for the rest of your life. Do not stop taking this medication without first talking to your doctor. Stopping suddenly may make your condition worse. Store at room temperature away from moisture and heat.

See also: Guanabenz dosage (in more detail)

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose symptoms may include extreme drowsiness, irritability, weak pulse, or fainting.

What should I avoid while taking guanabenz?

This medication may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.

Avoid getting up too fast from a sitting or lying position, or you may feel dizzy. Get up slowly and steady yourself to prevent a fall.

Avoid drinking alcohol. Guanabenz can increase the effects of alcohol.

Guanabenz side effects

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat. Call your doctor at once if you have a serious side effect such as:

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  very slow heart rate;

  
  


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  chest pain, severe headache, ringing in your ears; or

  
  


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  feeling like you might pass out.

  
  

Less serious side effects may include:

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  dizziness, drowsiness;

  
  


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  headache;

  
  


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  dry mouth; or

  
  


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  weakness.

  
  

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Guanabenz Dosing Information

Usual Adult Dose for Hypertension:

Initial dose: 4 mg orally twice a day, whether used alone or in combination with a thiazide diuretic.
Maintenance dose: 4 to 8 mg orally twice a day. The maximum dose studied is 32 mg twice a day, although doses this high are rarely needed.

What other drugs will affect guanabenz?

Cold or allergy medicine, sedatives, narcotic pain medicine, sleeping pills, muscle relaxers, and medicine for seizures, depression or anxiety can add to sleepiness caused by guanabenz. Tell your doctor if you regularly use any of these medicines, or any other blood pressure medications.

This list is not complete and other drugs may interact with guanabenz. Tell your doctor about all medications you use. This includes prescription, over-the-counter, vitamin, and herbal products. Do not start a new medication without telling your doctor.

More guanabenz resources

• Guanabenz Side Effects (in more detail)
• Guanabenz Dosage
• Guanabenz Use in Pregnancy & Breastfeeding
• Drug Images
• Guanabenz Drug Interactions
• Guanabenz Support Group
• 1 Review for Guanabenz - Add your own review/rating

• guanabenz Advanced Consumer (Micromedex) - Includes Dosage Information


• Guanabenz MedFacts Consumer Leaflet (Wolters Kluwer)


• Guanabenz Prescribing Information (FDA)

Compare guanabenz with other medications

• High Blood Pressure

Where can I get more information?

• Your pharmacist can provide more information about guanabenz.

See also: guanabenz side effects (in more detail)