What is the most important information I should know about doxazosin?

Doxazosin lowers blood pressure and may cause dizziness or fainting, especially when you first start taking it, or when you start taking it again. To avoid falling, take the first dose of doxazosin at bedtime. You may wish to continue taking this medication only at bedtime if it causes you to feel light-headed.

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

If you stopped taking doxazosin for any reason and have started taking it again, you may feel especially dizzy or light-headed after your first few doses.

Doxazosin can affect the pupils of your eyes during cataract surgery. If you have cataract surgery during your treatment with doxazosin, tell the surgeon ahead of time that you take doxazosin. Do not stop using the medication before surgery unless your surgeon tells you to.

What is doxazosin?

Doxazosin is in a group of drugs called alpha-adrenergic blockers. Doxazosin causes the blood vessels (veins and arteries) to relax and expand, improving blood flow. Doxazosin also relaxes muscles in the prostate and bladder neck, making it easier to urinate.

Doxazosin is used to treat hypertension (high blood pressure) and benign prostatic hyperplasia (enlarged prostate).

Doxazosin may also be used for purposes other than those listed in this medication guide.

What should I discuss with my doctor before taking doxazosin?

Doxazosin can affect the pupils of your eyes during cataract surgery. If you have cataract surgery during your treatment with doxazosin, tell the surgeon ahead of time that you take doxazosin. Do not stop using the medication before surgery unless your surgeon tells you to.

Before taking this medication, tell your doctor if you have liver disease, or a history of prostate cancer. You may need a dosage adjustment or special tests during therapy with doxazosin.

FDA pregnancy category C. This medication may be harmful to an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant during treatment.

It is not known whether doxazosin passes into breast milk or if it could harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.

How should I take doxazosin?

Take this medication exactly as it was prescribed for you. Do not take the medication in larger amounts, or take it for longer than recommended by your doctor. Your doctor may occasionally change your dose to make sure you get the best results from this medication.

Take each dose with a full glass of water.

Doxazosin lowers blood pressure and may cause dizziness or fainting, especially when you first start taking it, or when you start taking it again. To avoid falling, take the first dose of doxazosin at bedtime. You may wish to continue taking this medication only at bedtime if it causes you to feel light-headed.

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

If you stopped taking doxazosin for any reason and have started taking it again, you may feel especially dizzy or light-headed after your first few doses.

To be sure this medication is helping your condition, your blood pressure or prostate will need to be checked on a regular basis. It is important that you not miss any scheduled visits to your doctor.

If you are being treated for high blood pressure, keep using this medication even if you feel fine. High blood pressure often has no symptoms.

Store doxazosin at room temperature away from moisture and heat.

What happens if I miss a dose?

Take the missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and take the medicine at the next regularly scheduled time. Do not take extra medicine to make up the missed dose.

If you miss doses for several days in a row, call your doctor before taking any additional doses. You may need to use a lower dose of doxazosin for a short time.

What happens if I overdose?

Seek emergency medical attention if you think you have used too much of this medicine.

Symptoms of a doxazosin overdose may include drowsiness, fainting, or seizure (convulsions).

What should I avoid while taking doxazosin?

Doxazosin can cause side effects that may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be awake and alert.

Avoid drinking alcohol, which can increase some of the side effects of doxazosin.

Avoid using other medicines that make you sleepy (such as cold medicine, pain medication, muscle relaxers, and medicine for seizures, depression or anxiety). They can add to sleepiness caused by doxazosin.

What are the possible side effects of doxazosin?

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

Call your doctor at once if you have any of these serious side effects:

• fast or pounding heartbeats;
• feeling light-headed, fainting;
• swelling in your hands, ankles, or feet; or
• penis erection that is painful or lasts 4 hours or longer.

Other, less serious side effects may be more likely to occur, such as:

• weakness;
• headache;
• dizziness; or
• diarrhea, stomach pain.

Side effects other than those listed here may also occur. Talk to your doctor about any side effect that seems unusual or that is especially bothersome.

What other drugs will affect doxazosin?

There may be other drugs that can affect doxazosin. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor.

Where can I get more information?

Your pharmacist has additional information about doxazosin written for health professionals that you may read.

What does my medication look like?

Doxazosin is available with a prescription under the brand name Cardura. Other brand or generic formulations may also be available. Ask your pharmacist any questions you have about this medication, especially if it is new to you.

• Cardura 1 mg--white, oblong tablets
• Cardura 2 mg--yellow, oblong tablets
• Cardura 4 mg--orange, oblong tablets
• Cardura 8 mg--green, oblong tablets

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2003 Cerner Multum, Inc. Version: 4.05. Revision date: 7/6/06.