Prazosin
Generic Name: Prazosin (PRAZ-oh-sin)
Brand Name: Minipress
Prazosin is used for:
Treating high blood pressure and benign prostatic hyperplasia (BPH). It may also be used for other conditions as determined by your doctor.
Prazosin is an alpha-blocker. The exact way it works is unknown, but it is thought to block a chemical in the body, causing blood vessels and the muscles around the urethra to relax. This helps to lower blood pressure and to improve urinary symptoms associated with enlargement of the prostate (BPH).
Do NOT use Prazosin if:
- you are allergic to any ingredient in Prazosin
- you are taking modafinil
Contact your doctor or health care provider right away if any of these apply to you.
Before using Prazosin :
Some medical conditions may interact with Prazosin . Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:
- if you are pregnant, planning to become pregnant, or are breast-feeding
- if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
- if you have allergies to medicines, foods, or other substances
- if you have chest pain, heart disease, narcolepsy, or kidney problems
Some MEDICINES MAY INTERACT with Prazosin . Tell your health care provider if you are taking any other medicines, especially any of the following:
- Indomethacin because it may decrease Prazosin 's effectiveness
- Verapamil because it may increase the actions and the risk of Prazosin 's side effects
- Beta-blockers (eg, propranolol), bupivacaine, nifedipine, or phosphodiesterase type 5 inhibitors (eg, sildenafil) because their actions and the risk of their side effects may be increased by Prazosin
- Modafinil because its effectiveness may be decreased by Prazosin
This may not be a complete list of all interactions that may occur. Ask your health care provider if Prazosin may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.
How to use Prazosin :
Use Prazosin as directed by your doctor. Check the label on the medicine for exact dosing instructions.
- Take Prazosin by mouth with or without food.
- If you miss a dose of Prazosin , take it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once.
Ask your health care provider any questions you may have about how to use Prazosin .
Important safety information:
- Prazosin may cause dizziness, lightheadedness, or fainting after the first dose. Take the first dose at bedtime. If you get up during the night, sit up and stand slowly. Continue to sit up and stand slowly while you are taking Prazosin .
- Prazosin may cause dizziness, drowsiness, lightheadedness, or blurred vision. These effects may be worse if you take it with alcohol or certain medicines. Use Prazosin with caution. Do not drive or perform other possibly unsafe tasks until you know how you react to it.
- Prazosin may cause dizziness, lightheadedness, or fainting; alcohol, hot weather, exercise, or fever may increase these effects. To prevent them, sit up or stand slowly, especially in the morning. Sit or lie down at the first sign of any of these effects.
- Avoid engaging in any hazardous tasks for at least 24 hours after taking the first dose, missing several doses, increasing the dose, or taking other high blood pressure medications.
- Before drinking alcohol, discuss it with your doctor.
- Patients who take medicine for high blood pressure often feel tired or run down for a few weeks after starting treatment. Be sure to take your medicine even if you may not feel "normal." Tell your doctor if you develop any new symptoms.
- Use Prazosin with extreme caution in the ELDERLY; they may be more sensitive to its effects.
- Prazosin should not be used in CHILDREN; safety and effectiveness in children have not been confirmed.
- PREGNANCY and BREAST-FEEDING: If you become pregnant, contact your doctor. You will need to discuss the benefits and risks of using Prazosin while you are pregnant. Prazosin is found in breast milk. If you are or will be breast-feeding while you use Prazosin , check with your doctor. Discuss any possible risks to your baby.
Possible side effects of Prazosin :
All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:
Seek medical attention right away if any of these SEVERE side effects occur:Constipation; depression; dizziness; drowsiness; dry mouth; feeling of a whirling motion; flushing; frequent urination; headache; lack of energy; lightheadedness; nasal congestion; nausea; nervousness; nosebleed; stuffy nose; swelling; vomiting; weakness.
Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); blurred vision; fainting; pounding heartbeat; puffiness in hands or feet; rapid heartbeat.
This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088. You may also report side effects at http://www.fda.gov/medwatch.
If OVERDOSE is suspected:
Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center (http://www.aapcc.org), or emergency room immediately. Symptoms may include dizziness; weakness.
Proper storage of Prazosin :Store Prazosin at room temperature, between 68 and 77 degrees F (20 and 25 degrees C). Store away from heat, light, and moisture. Keep Prazosin out of the reach of children and away from pets.
General information:
- If you have any questions about Prazosin , please talk with your doctor, pharmacist, or other health care provider.
- Prazosin is to be used only by the patient for whom it is prescribed. Do not share it with other people.
- If your symptoms do not improve or if they become worse, check with your doctor.
This information is a summary only. It does not contain all information about Prazosin . If you have questions about the medicine you are taking or would like more information, check with your doctor, pharmacist, or other health care provider.
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More Prazosin resources:
Prazosin - Includes detailed dosage instructions.
Anxiety and Stress, High Blood Pressure, Heart Failure, Benign Prostatic Hyperplasia (BPH), Raynaud's Syndrome











