Minipress (Oral)

Prazosin is used by itself or with other medicines to treat high blood pressure (hypertension). High blood pressure puts extra strain on the heart and arteries. If it lasts for a long time, the heart and arteries may not work properly. This can harm the blood vessels in the brain, heart, and kidneys, leading to a stroke, heart failure, or kidney failure. High blood pressure may also raise the risk of heart attacks. Controlling blood pressure may help reduce the chances of these problems.

Prazosin is part of a group of medicines called antihypertensives. It works by relaxing the blood vessels, allowing blood to flow through them more easily. This helps to lower blood pressure. Your doctor may also use prazosin for other conditions.

This medicine is available only with your doctor's prescription.

It is very important that your doctor checks your progress at regular visits to ensure that this medicine is working properly. Blood and urine tests may be needed to check for unwanted effects.

Dizziness, lightheadedness, or fainting may happen after you use this medicine, especially when you get up from lying down or sitting. Getting up slowly may help reduce this problem. If you feel dizzy, lie down to avoid fainting. Then sit for a few moments before standing to prevent the dizziness from coming back.

You may also experience dizziness, lightheadedness, or fainting if you drink alcohol, stand for a long time, exercise, or if the weather is hot. While taking this medicine, be careful to limit the amount of alcohol you consume. Drink plenty of fluids if you exercise or sweat more than usual while using this medicine.

Prazosin may cause some people to feel dizzy, drowsy, or less alert than usual. Make sure you know how this medicine affects you before you drive, operate machines, or do anything else that could be dangerous if you are dizzy, drowsy, or not alert.

Ensure that any doctor or dentist treating you knows that you are using this medicine. This medicine may affect the results of certain medical tests.

Call your doctor immediately if you have a prolonged erection of the penis while using this medicine. It must be treated right away to prevent permanent impotence.

Do not take other medicines unless you have discussed them with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

In deciding to use a medicine, you and your doctor must consider the risks of taking the medicine against the benefits it may provide. For this medicine, keep the following in mind:

Allergies

Inform your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also, let your healthcare professional know if you have any other allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, carefully read the label or package ingredients.

Pediatric

Appropriate studies have not been done on how prazosin affects children. Safety and efficacy have not been established.

Geriatric

There is no information available on how prazosin affects elderly patients.

Breast Feeding

There are no adequate studies in women to determine the risk to infants when using this medication while breastfeeding. Consider the potential benefits against the risks before using this medication while breastfeeding.

Interactions with Medicines

Some medicines should not be used together at all, while in other cases, two different medicines may be used together even if there might be an interaction. In these situations, your doctor may need to adjust the dose or take other precautions. When taking this medicine, it is especially important for your healthcare professional to know if you are taking any of the medicines listed below. The following interactions are highlighted for their potential significance but are not all-inclusive.

Using this medicine with any of the following medicines is usually not recommended, but may be necessary in some cases. If both medicines are prescribed together, your doctor may adjust the dose or how often you use one or both of the medicines.

• Alfuzosin
• Asenapine
• Melphalan
• Silodosin
• Tadalafil
• Tamsulosin
• Vardenafil

Using this medicine with any of the following medicines may increase the risk of certain side effects, but using both may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

• Acebutolol
• Alprenolol
• Atenolol
• Betaxolol
• Bevantolol
• Bisoprolol
• Bucindolol
• Carteolol
• Carvedilol
• Celiprolol
• Dilevalol
• Esmolol
• Labetalol
• Levobunolol
• Mepindolol
• Metipranolol
• Metoprolol
• Nadolol
• Nebivolol
• Oxprenolol
• Penbutolol
• Pindolol
• Propranolol
• Semaglutide
• Sildenafil
• Sotalol
• Talinolol
• Tertatolol
• Timolol

Interactions with Food/Tobacco/Alcohol

Certain medicines should not be used around mealtime or with certain foods due to possible interactions. Using alcohol or tobacco with some medicines may also cause interactions. Discuss with your healthcare professional about using your medicine with food, alcohol, or tobacco.

Other Medical Problems

Having other medical problems might affect how you can use this medicine. Be sure to inform your doctor if you have any other medical issues, especially:

• Angina (chest pain) or
• Severe heart disease or
• Postural hypotension (low blood pressure)—Use with caution. This may worsen these conditions.

• Cataract surgery—A condition called Intraoperative Floppy Iris Syndrome (IFIS) has been reported in patients taking or recently taking this medicine during cataract surgery. You should inform your ophthalmologist (eye doctor) before your surgery if you are taking prazosin.

• Kidney disease—Use with caution. The effects may be stronger due to slower removal of the medicine from the body.

Along with its needed effects, Minipress (Oral) may cause some unwanted effects. Not all of these side effects may happen, but if they do, they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

More common

• Dizziness
• fast, irregular, pounding, or racing heartbeat or pulse
• sleepiness

Less common

• Blurred vision
• chills
• cold sweats
• dizziness, faintness, or lightheadedness when getting up from lying or sitting position
• swelling
• trouble breathing

Rare

• Bloating
• constipation
• darkened urine
• decreased interest in sexual intercourse
• fever
• inability to have or keep an erection
• indigestion
• loss in sexual ability, desire, drive, or performance
• loss of appetite
• nausea
• painful or prolonged erection of the penis for more than 4 hours
• pains in the stomach, side, or abdomen, possibly radiating to the back
• vomiting
• yellow eyes or skin

Incidence not known

• Arm, back, or jaw pain
• chest pain, discomfort, tightness, or heaviness
• confusion
• cough
• difficulty swallowing
• eye pain
• hives, itching, skin rash
• puffiness or swelling of the eyelids or around the eyes, face, lips or tongue
• slow or irregular heartbeat
• unusual tiredness or weakness

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to Minipress (Oral). Your health care professional may also have ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue, are bothersome, or if you have any questions about them:

More common

• Headache
• lack of energy
• unusual drowsiness, dullness, or feeling of sluggishness

Less common

• Bloody nose
• diarrhea
• discouragement
• dry mouth
• feeling of constant movement of self or surroundings
• feeling sad or empty
• increased need to urinate
• loss of interest or pleasure
• nervousness
• passing urine more often
• sensation of spinning
• stuffy nose
• trouble concentrating
• trouble sleeping

Rare

• Burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
• continuing ringing or buzzing or other unexplained noise in the ears
• difficulty in moving
• hearing loss
• increased sweating
• loss or thinning of the hair
• muscle pain or stiffness
• pain in the joints
• seeing, hearing, or feeling things that are not there

Incidence not known

• Feeling of warmth
• lack or loss of strength
• redness of the face, neck, arms and occasionally, upper chest
• swelling of the breasts or breast soreness in both females and males

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your health care professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

In the U.S.

• Minipress

Available Dosage Forms:

• Capsule

Therapeutic Class: Cardiovascular Agent

Pharmacologic Class: Alpha-1 Adrenergic Blocker

Take this medicine exactly as directed by your doctor. Your doctor will tell you how much of this medicine to use and how often. Your dose may need to be changed several times in order to find out what works best for you. Do not use more medicine or use it more often than your doctor tells you to.

In addition to the use of this medicine, treatment for your high blood pressure may include weight control and changes in the types of foods you eat, especially foods high in sodium (salt). Your doctor will tell you which of these are most important for you. You should check with your doctor before changing your diet.

Many patients who have high blood pressure will not notice any symptoms of the condition. In fact, many patients may feel normal. It is very important that you take your medicine exactly as directed and that you keep your appointments with your doctor even if you feel well.

Remember that this medicine will not cure your high blood pressure, but it does help control it. You must continue to take it as directed if you expect to lower your blood pressure and keep it down. You may have to take high blood pressure medicine for the rest of your life.

To help you remember to take your medicine, try to get into the habit of taking it at the same time each day.

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

• For oral dosage form (capsules):For high blood pressure: Adults—At first, 1 milligram (mg) 2 or 3 times a day. Your doctor will slowly increase your dose as needed. However, the dose is usually not more than 20 mg per day. Children—Use and dose must be determined by your doctor.

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.