Doxazosin (By mouth)
Treats problems with urination caused by an enlarged prostate (benign prostatic hyperplasia or BPH). Also used alone or in combination with other medicines to treat high blood pressure. This medicine is an alpha-blocker.
Cardura, Cardura XL
There may be other brand names for this medicine.
When This Medicine Should Not Be Used
You should not use this medicine if you have had an allergic reaction to doxazosin, or to similar medicines such as prazosin (Minipress®) or terazosin (Hytrin®).
How to Use This Medicine
Tablet, Long Acting Tablet
- Your doctor will tell you how much of this medicine to use and how often. Your dose may need to be changed several times in order to find out what works best for you. Do not use more medicine or use it more often than your doctor tells you to.
- Swallow the extended-release tablet whole. Do not crush, break, or chew it.
- While taking the extended-release form of this medicine, part of the tablet may pass into your stools. This is normal and is nothing to worry about.
- Cardura® XL should be taken each day with breakfast. The regular-release tablet can be taken in the morning or in the evening, with or without food.
If a dose is missed:
- If you miss a dose or forget to use your medicine, use it as soon as you can. If it is almost time for your next dose, wait until then to use the medicine and skip the missed dose. Do not use extra medicine to make up for a missed dose.
How to Store and Dispose of This Medicine
- Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.
- Ask your pharmacist, doctor, or health caregiver about the best way to dispose of any outdated medicine or medicine no longer needed.
- Keep all medicine away from children and never share your medicine with anyone.
Drugs and Foods to Avoid
Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.
- Make sure your doctor knows if you are using other medicines such as atazanavir (Reyataz®), clarithromycin (Biaxin®), indinavir (Crixivan®), itraconazole (Sporanox®), ketoconazole (Nizoral®), nefazodone (Serzone®), nelfinavir (Viracept®), ritonavir (Norvir®), saquinavir (Fortovase®, Invirase®), telithromycin (Ketek®), or voriconazole (Vfend®). Tell your doctor if you are also taking medicine to lower blood pressure (such as atenolol, hydrochlorothiazide [HCTZ], lisinopril, metoprolol, quinapril, Accupril®, Cozaar®, Diovan®, Lotrel®, Norvasc®, Toprol®, or Zestril®) or medicine for erectile dysfunction (such as sildenafil, tadalafil, vardenafil, Cialis®, Levitra®, or Viagra®).
Warnings While Using This Medicine
- Make sure your doctor knows if you are pregnant or breastfeeding, or if you have liver disease, heart disease, low blood pressure, prostate cancer, or abdominal or stomach problems such as blocked bowels.
- Before you have eye surgery for a cataract (clouding of the eye), tell the ophthalmologist (eye doctor) that you are taking this medicine.
- This medicine may make you dizzy, drowsy, faint, or lightheaded. Avoid driving, using machines, or doing anything else that could be dangerous if you are dizzy or not alert. Getting up slowly may also help.
- If you stop using this medicine, your blood pressure may go up. High blood pressure usually has no symptoms. Even if you feel well, do not stop using the medicine without asking your doctor.
- This medicine lowers the number of some types of blood cells in your body. Because of this, you may bleed or get infections more easily. To help with these problems, avoid being near people who are sick or have infections. Wash your hands often. Stay away from rough sports or other situations where you could be bruised, cut, or injured. Brush and floss your teeth gently. Be careful when using sharp objects, including razors and fingernail clippers.
- Your doctor will need to check your progress at regular visits while you are using this medicine. Be sure to keep all appointments.
Possible Side Effects While Using This Medicine
Call your doctor right away if you notice any of these side effects:
- Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
- Chest pain.
- Fast, slow, pounding, or uneven heartbeat.
- Fever, chills, cough, sore throat, and body aches.
- Lightheadedness, dizziness, or fainting.
- Numbness or weakness in your arm or leg, or on one side of your body.
- Pain on urination, change in how much or how often you urinate, or red or dark brown urine.
- Painful, prolonged erection of your penis.
- Trouble with breathing.
- Unusual bleeding or bruising.
- Yellowing of your skin or the whites of your eyes.
If you notice these less serious side effects, talk with your doctor:
- Agitation or nervousness.
- Breast enlargement or swelling.
- Changes in vision.
- Hair loss.
- Headache, back pain, muscle pain, joint pain, or muscle cramps.
- Loss of appetite.
- Nausea, vomiting, diarrhea, stomach pain, or upset stomach.
- Problems having sex.
- Skin rash or itching.
- Tingling, prickling, or numbness of the skin.
- Tiredness or weakness.
- Warmth or redness in your face, neck, arms, or upper chest.
If you notice other side effects that you think are caused by this medicine, tell your doctor
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088
- Last Reviewed on 06/12/2013
The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- 2013 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.
This page was last updated: September 18, 2013