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Minipress Side Effects

Generic Name: prazosin

Note: This document contains side effect information about prazosin. Some of the dosage forms listed on this page may not apply to the brand name Minipress.

In Summary

Common side effects of Minipress include: dizziness. Other side effects include: syncope and drowsiness. See below for a comprehensive list of adverse effects.

For the Consumer

Applies to prazosin: oral capsule, oral tablet

Along with its needed effects, prazosin (the active ingredient contained in Minipress) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

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

More common
  • Dizziness or lightheadedness, especially when getting up from a lying or sitting position
  • fainting (sudden)
Less common
  • Loss of bladder control
  • pounding heartbeat
  • swelling of the feet or lower legs
Rare
  • Chest pain
  • trouble breathing
Incidence not known
  • Painful or prolonged erection of the penis

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

More common
  • Drowsiness
  • headache
  • lack of energy
Less common
  • Dryness of the mouth
  • nervousness
  • unusual tiredness or weakness
Rare
  • Frequent urge to urinate
  • nausea

For Healthcare Professionals

Applies to prazosin: compounding powder, oral capsule

General

The most common adverse reactions were postural hypotension, dizziness, headache, drowsiness, lack of energy, weakness, palpitations, and nausea.[Ref]

Cardiovascular

Very common (10% or more): Postural hypotension (up to 14%)
Common (1% to 10%): Palpitations, tachycardia, orthostatic hypotension
Uncommon (0.1% to 1%): Angina pectoris
Rare (less than 0.1%): Bradycardia, flushing, hypotension, vasculitis
Frequency not reported: Angina exacerbation, myocardial infarction[Ref]

Nervous system

Very common (10% or more): Dizziness (up to 10.3%)
Common (1% to 10%): Drowsiness, headache, faintness, syncope, vertigo
Uncommon (0.1% to 1%): Paresthesia, tinnitus
Rare (less than 0.1%): Narcolepsy worsened[Ref]

Other

Common (1% to 10%): Lack of energy, weakness, asthenia
Rare (less than 0.1%): Fever, pain
Frequency not reported: Malaise[Ref]

Gastrointestinal

Common (1% to 10%): Constipation, diarrhea, dry mouth, nausea, vomiting
Uncommon (0.1% to 1%): Abdominal discomfort and/or pain
Rare (less than 0.1%): Pancreatitis[Ref]

Respiratory

Common (1% to 10%): Dyspnea, nasal congestion, epistaxis[Ref]

Psychiatric

Common (1% to 10%): Depression, nervousness
Uncommon (0.1% to 1%): Insomnia
Rare (less than 0.1%): Hallucinations[Ref]

Ocular

Common (1% to 10%): Blurred vision, sclera reddened
Uncommon (0.1% to 1%): Eye pain
Frequency not reported: Pigmentary mottling, serious retinopathy, cataract development, cataract disappearance[Ref]

Genitourinary

Common (1% to 10%): Urinary frequency, impotence
Rare (less than 0.1%): Incontinence, priapism[Ref]

Dermatologic

Common (1% to 10%): Rash
Uncommon (0.1% to 1%): Diaphoresis, pruritus, urticaria
Rare (less than 0.1%): Alopecia, lichen planus[Ref]

Metabolic

Common (1% to 10%): Edema[Ref]

Musculoskeletal

Uncommon (0.1% to 1%): Arthralgia[Ref]

Immunologic

Rare (less than 0.1%): Allergic reaction, positive antinuclear antibody titer[Ref]

Endocrine

Rare (less than 0.1%): Gynecomastia[Ref]

Hepatic

Rare (less than 0.1%): Liver function abnormalities[Ref]

References

1. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0

2. Cerner Multum, Inc. "Australian Product Information." O 0

3. "Product Information. Minipress (prazosin)." Pfizer US Pharmaceuticals, New York, NY.

Some side effects of Minipress may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. Drugs.com does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. 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 substances you are taking, check with your doctor, nurse, or pharmacist.

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