• Basic Info
• Top Questions
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What is prazosin?
Prazosin is in a class of drugs called alpha-adrenergic blockers. Prazosin causes the blood vessels (veins and arteries) to relax and expand, which allows blood to pass more easily through them. Prazosin is used to treat hypertension (high blood pressure). Prazosin may be used for purposes other than those listed in this medication guide.

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What is the price of this medication and similar alternatives?

This pricing information is subject to change at the sole discretion of DS Pharmacy. For the most current and up-to-date pricing information, please visit drugstore.com.

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What are the possible side effects of prazosin?

If you experience any of the following serious side effects, stop taking prazosin and seek emergency medical attention or contact your doctor immediately:

• an allergic reaction (difficulty breathing; closing of your throat; swelling of your lips, tongue, or face; or hives);

• an increased heartbeat;

• shortness of breath or chest pain; or

• a rash.

Other, less serious side effects may be more likely to occur. Continue to take prazosin and talk to your doctor if you experience

• vivid dreams;

• dizziness or drowsiness;

• weakness, fatigue, or ill feeling;

• nausea, vomiting, diarrhea, constipation, abdominal pain, or decreased appetite;

• fluid retention or slight weight gain;

• joint or muscle aches;

• headache, irritability, or depression;

• increased urination;

• decreased sex drive; or

• numbness or tingling in your hands, feet, arms, or legs.

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.

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How should I take prazosin?
Take prazosin exactly as directed by your doctor. If you do not understand these directions, ask your pharmacist, nurse, or doctor to explain them to you. Take each dose with a full glass of water. To avoid falling, take the first dose at bedtime. Prazosin may cause dizziness. It is a good idea to take every dose at bedtime, if possible. Use caution when you stand or sit up from a lying position, especially if you wake up during the night. Dizziness may occur when changing positions. Do not stop taking this drug suddenly even if you feel better. Stopping suddenly could cause your blood pressure to increase.

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What is the most important information I should know about prazosin?
To avoid falling, take the first dose at bedtime. Prazosin may cause dizziness. It is a good idea to take every dose at bedtime, if possible. Use caution when you stand or sit up from a lying position, especially if you wake up during the night. Dizziness may occur when changing positions. Do not stop taking this drug suddenly even if you feel better. Stopping suddenly could cause your blood pressure to increase.

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What happens if I miss a dose?
Take the missed dose as soon as you remember. However, if it is almost time for the next dose, skip the dose you missed and take only the next regularly scheduled dose. Do not take a double dose of this medication. A double dose could cause your blood pressure to become severely low. If you miss doses for several days in a row, call your doctor before taking any additional doses. You may need to restart treatment with a lower dose.

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What other drugs will affect prazosin?
Talk to your doctor and pharmacist before taking any prescription or over-the-counter medicines, including herbal supplements, during treatment with prazosin.

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Can I take this if I am pregnant or trying to get pregnant or if I am breastfeeding?

Prazosin has been assigned to pregnancy category C by the FDA. Animal studies have shown evidence of decreased litter size after prazosin was administered at doses more than 225 times the maximum recommended dose in humans (on a per kg basis). No controlled data are available in human pregnancy, but studies in which prazosin was administered during human pregnancy show only maternal tachycardia and no teratogenic effects. Prazosin should only be given during pregnancy when benefit outweighs risk.

Use of prazosin combined with oxprenolol during human pregnancy has been reported. The population studied was 44 pregnant women, 25 of whom had severe hypertension, and 19 of whom had severe hypertension, edema, and proteinuria. There were three intrauterine deaths that were considered related to underlying diseases and not to drug therapy. One infant who suffered intrauterine growth retardation died postpartum after elective Cesarean section at 27 weeks gestation. This growth retardation was an expected finding given the underlying condition of the mother and the population studied. The overall fetal survival rate of 78% was considered acceptable relative to untreated hypertensive pregnancy fetal survival rates. In short, no definite causative connection has been made between adverse sequelae to the fetus and prazosin.

The manufacturer states that small amounts of prazosin are excreted into human milk. The manufacturer recommends that caution be used when administering prazosin to nursing women.

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Who should NOT use this medication?

Known hypersensitivity to prazosin, quinazolines (e.g., doxazosin, terazosin), or any ingredient in the formulation.

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What does my medication look like?
Prazosin is available with a prescription under the brand name Minipress. 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. Minipress 1 mg--white capsules Minipress 2 mg--pink/white capsules Minipress 5 mg--blue/white capsules

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What happens if I overdose?
Seek emergency medical attention. Symptoms of a prazosin overdose include weakness, dizziness, and fainting; a weak, fast pulse; cold, clammy skin; and possibly loss of consciousness or coma.

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Who should not take prazosin?
Before taking this medication, tell your doctor if you have any type of kidney or liver disease. You may need a dosage adjustment or special monitoring during therapy with prazosin. Prazosin is in the FDA pregnancy category C. This means that it is not known whether prazosin will harm an unborn baby. Do not take prazosin without first talking to your doctor if you are pregnant. Prazosin passes into breast milk and may affect a nursing baby. Do not take prazosin without first talking to your doctor if you are breast-feeding a baby.

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Can I stop taking the medication if I feel better?
Even though you may feel better you should not stop taking your high blood pressure medication without first checking with your healthcare provider.

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I am on so many medications; do I have to take them all?
This is called polypharmacy—many different medications being used at the same time by one person. Sometimes, being on multiple medications is acceptable and appropriate but at other times it may be problematic. If you are receiving your medications from multiple physicians you need to ensure that they all know what medications you are taking. The best way to do this is to make a list of all the medications you are currently using, including all nutritional supplements, homeopathic remedies, vitamins and over-the-counter drugs (if possible, also include all the diseases you have been diagnosed with). Give a copy to every doctor who takes care of you so they have it on file, this way they can avoid duplicating medications and perhaps even try to consolidate some. After every doctor's visit remember to update the list accordingly. Also, as much as you possibly can, try to use the same pharmacy to fill all your prescriptions, this way any potential drug interactions can be caught and averted.

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Where can I get more information?
More Information

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