Prazosin Dosage

Medically reviewed by Drugs.com. Last updated on Nov 16, 2023.

Applies to the following strengths: 1 mg; 2 mg; 5 mg

Usual Adult Dose for Hypertension

Initial dose: 1 mg orally 2 or 3 times a day
Maintenance dose: 1 to 20 mg orally per day in divided doses

Comments:

Titrate slowly as determined by blood pressure response.
Therapeutic dosages usually range from 6 to 15 mg per day in divided doses.
Total daily doses greater than 20 mg usually do not increase efficacy, but some patients may benefit from daily doses up to 40 mg per day in divided doses.

Data not available

Data not available

Adding a diuretic or another antihypertensive agent:

Coadministration with phosphodiesterase-5 (PDE-5) inhibitors:

Safety and efficacy have not been established in children.

Consult WARNINGS section for additional precautions.

Data not available

Storage requirements: Protect from light.

Monitoring:

Cardiovascular: Blood pressure (following the initial dose and dose adjustments)

Patient advice:

Advise patients how to avoid symptoms associated with lowering of blood pressure (e.g., dizziness, lightheadedness) and what to do if they occur. Also, encourage patients to avoid situations where injury could result if these symptoms occur.
Inform male patients about the seriousness of priapism and instruct them to seek immediate medical attention if it occurs.
Advise patients to report current or previous use of this drug to their ophthalmologist.