Cardura (doxazosin)

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Brand Name

Cardura {Pfizer}

Generic Name

doxazosin, pronounced dox AY zo sin


What is Cardura?

Cardura is used to treat hypertension (high blood pressure) or to help men that have benign prostatic hyperplasia, as it can help to improve urination. Cardura relaxes the veins and arteries so that blood can more easily pass through them and also helps to relax the muscles in your bladder neck and prostrate, making it easier for you to urinate. Cardura may be prescribed for reasons not stated in this medication guide.


Key Facts About Cardura

Cardura is in a group of medications called alpha-adrenergic blockers, and it helps to relax your veins and arteries so that blood can more easily pass through them.

Cardura works by reducing the swelling of your prostate gland, which when swollen, may block the flow of urine. Cardura helps to relax the muscles of the prostate and increase your urine flow.

Women and children should not take Cardura, as this drug is prescribed for men only.

You may experience a sudden drop in blood pressure when taking Cardura, especially after the first dose. This drop in your blood pressure can cause dizziness, lightheadedness or fainting. Be sure to rise slowly from a bed or chair each time until you determine how you react to Cardura.

You should not drive or take part in any potentially hazardous activities until you are comfortable with your dose of Cardura and used to the side effects.


Before You Take Cardura

If you are allergic to doxazosin or similar medications like alfuzosin (Uroxatral), prazosin (Minipress), silodosin (Rapaflo), tamsulosin (Flomax) or terazosin (Hytrin) you should not take Cardura.

Tell your doctor if you have liver disease or a history of prostate cancer.

You should be screened for Prostate Cancer before starting treatment with Cardura. Benign prostatic hyperplasia (BPH) frequently exists alongside prostate cancer, so you should be screened not only before you start Cardura, but also during your treatment at regular intervals.

Tell your doctor about all of the prescription, over-the-counter, and herbal medications that you take before you start treatment with Cardura.

Inform your doctor if you are taking diuretics.

Let your doctor know if you are planning to you have cataract surgery before you begin taking Cardura. This medication can affect your pupils during cataract surgery. Do not stop taking Cardura without speaking to your doctor first.


Cardura Drug Interactions

You should inform your doctor if you are taking any of the following:

  • blood pressure medications
  • diuretics
  • erectile dysfunction (ED) medications like sildenafil (Viagra), tadalafil (Cialis), or vardenafil (Levitra)

Other drugs you take that are not listed may interact with Cardura. You should tell your doctor about all of the medications you use. This includes prescription drugs, vitamins, supplements and herbal products, and over the counter medications. You should not begin taking a new medication without telling your doctor first.


Directions for Taking Cardura

Your doctor will prescribe your dose of Cardura based on your medical history and condition. Be sure to follow your doctor’s instructions exactly. Do not change your dosage of Cardura or stop taking Cardura without your doctor’s approval.

Cardura tablets should be swallowed whole, and not broken, chewed or crushed.

Cardura should be stored at room temperature, away from heat and light.

If you miss a dose of Cardura you should attempt to take the missed dose as soon as you remember. However, if it is almost time for your next scheduled dose do not take the missed dose in addition to your regular dose. If you miss several days of Cardura call your doctor, as you may need a dose adjustment.


Cardura Side Effects

If you experience any of the following adverse effects you should stop taking Cardura and seek emergency medical help immediately;

  • allergic reaction such as hives, itching or a rash
  • difficulty breathing, feeling like you might pass out
  • heartbeats that are fast, fluttering or pounding
  • penis erection that lasts 4 hours or longer and may be painful
  • swelling of your ankles, hands or feet

Less serious side effects of Cardura may include:

  • dizziness
  • drowsiness
  • headache
  • nausea
  • runny nose

It should be noted that this is not a complete list of possible side effects of Cardura. You should contact your physician for a complete list and medical advice regarding these effects.


Cardura Description and Dosing

Cardura is available as a tablet in dosages of 1 mg, 2 mg, 4 mg and 8 mg. Each scored tablet can be identified by color as follows:

1 mg is white.

2 mg is yellow.

4 mg is orange.

8 mg is green.

You should consult your doctor for specific dosing pertaining to you. Do not attempt to alter or change your dose without your physician’s consent.

If you suspect that you have overdosed with Cardura you should seek emergency help immediately.


Ingredients in Cardura

The primary active ingredient in Cardura is doxazosin mesylate. Inactive ingredients in all tablets are microcrystalline cellulose, lactose, sodium starch glycolate, magnesium stearate and sodium lauryl sulfate. The 2 mg tablet contains D & C yellow 10 and FD & C yellow 6; the 4 mg tablet contains FD & C yellow 6; the 8 mg tablet contains FD & C blue 10 and D & C yellow 10.

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The information contained in this drug guide is intended as an educational resource only. This guide is not exhaustive and does not contain all available information about this drug.This guide is not intended as medical advice for individual conditions or treatment.

The information provided in this guide does not replace the need for the advice and services of medical professionals or the need for medical examination. Always talk to your physician or pharmacist before taking any prescription medication or over the counter drugs (including any supplements) or before making any changes to your treatment. Only your doctor, nurse or pharmacist can provide you with safe and effective advice regarding your drug treatment.

The use of the information in this guide is at your sole risk. This information is provided "AS IS" with no warranties to accuracy or timeliness.

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