Doxazosin
(dox ay’ zoe sin)
Why is this medication prescribed?
Doxazosin is used to treat the symptoms of an enlarged prostate (benign prostatic hyperplasia or BPH), which include difficulty urinating (hesitation, dribbling, weak stream, and incomplete bladder emptying), painful urination, and urinary frequency and urgency. It is also used alone or in combination with other medications to treat high blood pressure. Doxazosin is in a class of medications called alpha-blockers. It relieves the symptoms of BPH by relaxing the muscles of the bladder and prostate. It lowers blood pressure by relaxing the blood vessels so that blood can flow more easily through the body.
How should this medicine be used?
Doxazosin comes as a tablet to take by mouth. It is usually taken with or without food once a day in the morning or in the evening. To help you remember to take doxazosin, take it around the same time every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take doxazosin exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.
Your doctor will start you on a low dose of doxazosin and gradually increase your dose, not more than once every 1 to 2 weeks. If you stop taking doxazosin for a few days or longer, your doctor will have to start you again on the lowest dose and gradually increase your dose.
Doxazosin controls high blood pressure and the symptoms of BPH but does not cure them. Continue to take doxazosin even if you feel well. Do not stop taking doxazosin without talking to your doctor.
Other uses for this medicine
Doxazosin also is used sometimes with other medications to treat congestive heart failure. Talk to your doctor about the possible risks of using this medication for your condition.
This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.
What special precautions should I follow?
Before taking doxazosin,
- tell your doctor and pharmacist if you are allergic to doxazosin, prazosin (Minipress), terazosin (Hytrin), or any other medications.
- tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking. Be sure to mention any of the following: other medications for high blood pressure. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
- tell your doctor if you have or have ever had liver disease.
- tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking doxazosin, call your doctor.
- if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking doxazosin.
- you should know that doxazosin may make you drowsy or dizzy. Do not drive a car or operate machinery for 24 hours after the first time you take doxazosin or after your dose is increased.
- you should know that doxazosin may cause dizziness, lightheadedness, and fainting when you get up too quickly from a lying position. This is more common when you first start taking doxazosin and when your dose is increased. To avoid this problem, get out of bed slowly, resting your feet on the floor for a few minutes before standing up. If you experience these symptoms, sit or lie down.
What special dietary instructions should I follow?
Your doctor may prescribe a low-salt or low-sodium diet. Follow these directions carefully.
What should I do if I forget a dose?
Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one. Check with your doctor if you have missed two or more doses.
What side effects can this medication cause?
Doxazosin may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- dizziness
- lightheadedness
- excessive tiredness
- swelling of the hands, feet, ankles, or lower legs
- shortness of breath
- dry mouth
- drowsiness
- muscle or joint pain or weakness
- abnormal vision
- runny nose
- decreased sexual ability
Some side effects can be serious. The following symptoms are uncommon, but if you experience any of them, call your doctor immediately:
- rapid, pounding, or irregular heartbeat
- fainting
- painful erection of the penis that lasts for hours
Doxazosin may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.
If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration’s (FDA) MedWatch Adverse Event Reporting program online [at http://www.fda.gov/MedWatch/report.htm] or by phone [1-800-332-1088].
What storage conditions are needed for this medicine?
Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom). Throw away any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.
In case of emergency/overdose
In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.
Symptoms of overdose may include:
- dizziness
- lightheadedness
- fainting
- seizure
What other information should I know?
Keep all appointments with your doctor. Your blood pressure should be checked regularly to determine your response to doxazosin.
Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.
Brand names
|
Last Revised - 07/01/2003