Cardura XL is an alpha-adrenergic (AL-fa ad-ren-ER-jik) blockers. This medicine 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.

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

The extended-release form of doxazosin (Cardura XL) is for use only in treating benign prostatic hyperplasia and should not be used to treat hypertension.

Cardura XL may also be used for purposes not listed in this medication guide.

Follow all directions on your medicine label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.

Follow all directions on your prescription label. Your doctor may occasionally change your dose. Do not use this medicine in larger or smaller amounts or for longer than recommended.

Cardura XL lowers blood pressure and may cause dizziness or fainting, especially when you first start taking it, or when you start taking it again.

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

Call your doctor if you have severe dizziness or feel like you might pass out.

While using Cardura XL, your blood pressure or prostate may need to be checked often.

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

If you are being treated for high blood pressure, keep using this medicine even if you feel well. High blood pressure often has no symptoms. You may need to use blood pressure medicine for the rest of your life.

Store at room temperature away from moisture and heat.

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

To make sure Cardura XL is safe for you, tell your doctor if you have:

• a blockage in your digestive tract (stomach or intestines);

• severe constipation;

• liver disease; or

• low blood pressure.

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

It is not known whether this medicine will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

It is not known whether doxazosin passes into breast milk or if it could harm a nursing baby. You should not breast-feed while using this medicine.

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, call your doctor before restarting the medication. You may need a lower dose.

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

Overdose symptoms may include extreme dizziness or fainting.

Cardura XL 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.

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

Drinking alcohol with Cardura XL can cause side effects.

Get emergency medical help if you have signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Cardura XL may cause serious side effects. Call your doctor at once if you have:

• a light-headed feeling, like you might pass out;

• severe ongoing stomach pain or bloating;

• new or worsening chest pain;

• trouble breathing; or

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

Common side effects of Cardura XL may include:

• low blood pressure, dizziness;

• drowsiness;

• headache; or

• feeling weak or tired.

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.

Tell your doctor about all your current medicines and any you start or stop using, especially:

• an antibiotic;

• an antidepressant;

• medicine to treat HIV or AIDS; or

• sildenafil (Viagra) or other erectile dysfunction medicines.

This list is not complete. Other drugs may interact with doxazosin, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.