Cardura

Generic Name: doxazosin (dox AY zo sin)

Brand Names: Cardura, Cardura XL

What is doxazosin?

Doxazosin is in a group of drugs called alpha-adrenergic (AL-fa ad-ren-ER-jik) blockers. Doxazosin relaxes your veins and arteries so that blood can more easily pass through them. It also relaxes the muscles in the prostate and bladder neck, making it easier to urinate.

Doxazosin is used to treat hypertension (high blood pressure), or to improve urination in men with benign prostatic hyperplasia (enlarged prostate).

Doxazosin may also be used for other purposes not listed in this medication guide.

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

You should not use this medication if you are allergic to doxazosin or similar medicines such as alfuzosin (Uroxatral), prazosin (Minipress), silodosin (Rapaflo), tamsulosin (Flomax), or terazosin (Hytrin). Doxazosin may cause dizziness or fainting, especially when you first start taking it or when you start taking it again. Be careful if you drive or do anything that requires you to be alert. Avoid standing for long periods of time or becoming overheated during exercise and in hot weather. Avoid getting up too fast from a sitting or lying position, or you may feel dizzy. If you stop taking doxazosin for any reason, call your doctor before you start taking it again. You may need a dose adjustment.

Doxazosin can affect your pupils during cataract surgery. Tell your eye surgeon ahead of time that you are using this medication. Do not stop using doxazosin before surgery unless your surgeon tells you to.

Tell your doctor about all other medications you use, especially other blood pressure medications including diuretics (water pills).

What should I discuss with my doctor before taking doxazosin?

You should not use this medication if you are allergic to doxazosin or similar medicines such as alfuzosin (Uroxatral), prazosin (Minipress), silodosin (Rapaflo), tamsulosin (Flomax), or terazosin (Hytrin).

If you have liver disease or a history of prostate cancer, you may need a dose adjustment or special tests to safely take doxazosin.

Doxazosin can affect your pupils during cataract surgery. Tell your eye surgeon ahead of time that you are using this medication. Do not stop using doxazosin before surgery unless your surgeon tells you to.

FDA pregnancy category C. It is not known whether doxazosin 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 doxazosin 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 doxazosin?

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.

Your doctor may occasionally change your dose to make sure you get the best results.

Doxazosin lowers blood pressure and may cause dizziness or fainting, especially when you first start taking it, or when you start taking it again. Call your doctor if you have severe dizziness or feel like you might pass out.

You may feel very dizzy when you first wake up. Be careful when standing or sitting up from a lying position.

If you stop taking doxazosin for any reason, call your doctor before you start taking it again. You may need a dose adjustment.

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

If you are being treated for high blood pressure, keep using this medication 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.

Some things can cause your blood pressure to get too low. This includes vomiting, diarrhea, heavy sweating, heart disease, dialysis, a low-salt diet, or taking diuretics (water pills). Tell your doctor if you have a prolonged illness that causes diarrhea or vomiting.

Store at room temperature away from moisture and heat.

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.

If you miss your doses for several days in a row, contact your doctor before restarting the medication. You may need a lower 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 dizziness or fainting.

What should I avoid while taking doxazosin?

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

To prevent dizziness, avoid standing for long periods of time or becoming overheated during exercise and in hot weather.

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.

Drinking alcohol can increase certain side effects of doxazosin.

Doxazosin side effects

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty 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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  feeling like you might pass out;

  
  


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  fast or pounding heartbeats, fluttering in your chest;

  
  


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  trouble breathing;

  
  


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  swelling in your hands, ankles, or feet; or

  
  


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  penis erection that is painful or lasts 4 hours or longer.

  
  

Less serious side effects may include:

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  mild dizziness;

  
  


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  tired feeling, drowsiness;

  
  


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  headache;

  
  


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  nausea; or

  
  


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  runny nose.

  
  

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.

What other drugs will affect doxazosin?

Tell your doctor about all other medications you use, especially:

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  sildenafil (Viagra, Revatio)

  
  


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  tadalafil (Cialis);

  
  


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  vardenafil (Levitra); or

  
  


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  other blood pressure medications, including diuretics (water pills).

  
  

This list is not complete and other drugs may interact with doxazosin. 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 Cardura resources

• Cardura Side Effects (in more detail)
• Cardura Use in Pregnancy & Breastfeeding
• Drug Images
• Cardura Drug Interactions
• Cardura Support Group
• 3 Reviews for Cardura - Add your own review/rating

• Cardura Monograph (AHFS DI)


• Cardura Prescribing Information (FDA)


• Cardura Consumer Overview


• Cardura Advanced Consumer (Micromedex) - Includes Dosage Information


• Cardura MedFacts Consumer Leaflet (Wolters Kluwer)


• Doxazosin Prescribing Information (FDA)


• Cardura XL Prescribing Information (FDA)


• Cardura XL Extended-Release Tablets MedFacts Consumer Leaflet (Wolters Kluwer)

Compare Cardura with other medications

• Benign Prostatic Hyperplasia
• High Blood Pressure
• Raynaud's Syndrome

Where can I get more information?

• Your pharmacist can provide more information about doxazosin.

See also: Cardura side effects (in more detail)