What is this medication?

DOXAZOSIN (dox AY zoe sin) is an alpha blocker. It treats high blood pressure in both men and women. It also helps treat benign prostatic hyperplasia (BPH) in men.

This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.

COMMON BRAND NAME(S): Cardura

What should I tell my care team before I take this medication?

They need to know if you have any of the following conditions:

  • kidney or liver disease
  • low blood pressure
  • an unusual or allergic reaction to doxazosin, other medicines, foods, dyes, or preservatives
  • pregnant or trying to get pregnant
  • breast-feeding

How should I use this medication?

Take this drug by mouth. Take it as directed on the prescription label at the same time every day. You can take it with or without food. If it upsets your stomach, take it with food. Keep taking it unless your health care provider tells you to stop.

Talk to your health care provider about the use of this drug in children. Special care may be needed.

Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.

NOTE: This medicine is only for you. Do not share this medicine with others.

What if I miss a dose?

If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.

What may interact with this medication?

  • cimetidine
  • medicines for colds or hay fever
  • medicines for overactive bladder
  • sildenafil
  • tadalafil
  • vardenafil

This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.

What should I watch for while using this medication?

Visit your doctor or health care professional for regular checks on your progress. Check your blood pressure regularly. Ask your doctor or health care professional what your blood pressure should be and when you should contact him or her.

Drowsiness and dizziness are more likely to occur after the first dose, after an increase in dose, or during hot weather or exercise. These effects can decrease once your body adjusts to this medicine. Do not drive, use machinery, or do anything that needs mental alertness until you know how this drug affects you. Do not stand or sit up quickly, especially if you are an older patient. This reduces the risk of dizzy or fainting spells. Alcohol can make you more drowsy and dizzy. Avoid alcoholic drinks.

Do not treat yourself for coughs, colds, or pain while you are taking this medicine without asking your doctor or health care professional for advice. Some ingredients may increase your blood pressure.

Your mouth may get dry. Chewing sugarless gum or sucking hard candy, and drinking plenty of water may help. Contact your doctor if the problem does not go away or is severe.

If you are going to have eye surgery for cataracts, tell your doctor or health care professional you are taking this medicine. A condition called Intraoperative Floppy Iris Syndrome (IFIS) can happen if you have taken this medicine.

For males, contact your doctor or health care professional right away if you have an erection that lasts longer than 4 hours or if it becomes painful. This may be a sign of a serious problem and must be treated right away to prevent permanent damage.

What side effects may I notice from receiving this medication?

Side effects that you should report to your doctor or health care professional as soon as possible:

  • allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue
  • breathing problems
  • changes in vision
  • chest pain
  • fast or irregular heartbeat
  • feeling faint or lightheaded, falls
  • males: prolonged or painful erection
  • numbness in hands or feet
  • swelling of the legs or ankles
  • unusually weak or tired

Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):

  • headache
  • nausea

This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Where should I keep my medication?

Keep out of the reach of children and pets.

Store at room temperature between 15 and 30 degrees C (59 and 86 degrees F). Throw away any unused drug after the expiration date.

NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.

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