Prazosin is an antihypertensive drug developed by the U.S. Food And Drug Administration and initially approved for treating hypertension.

Prazosin is used to treat high blood pressure (hypertension) and benign prostatic hyperplasia (BPH), a condition in which the prostate gland enlarges, causing urinary symptoms. It is sometimes prescribed off-label to manage nightmares associated with post-traumatic stress disorder (PTSD).

Take the Prazosin as your physician advises. Do not crush, chew, or open the medicine. Your physician will decide the correct dosage and duration based on age, body weight, and disease condition. Only stop taking the tablet if your doctor advises you to stop.

The side effects known to occur commonly during the treatment with  Prazosin are swelling of ankles, legs, or feet, feeling faint or dizzy, particularly on standing up, headache, drowsiness, palpitations

lack of energy, weakness, nervousness, constipation or diarrhea, dry mouth, blurred vision, nasal stiffness, and an increase in the frequency of urine.

Do not take this drug if you are allergic to it, other similar drugs called quinazoline drugs, or any of the ingredients in the medicine. This drug is not recommended in individuals under 12 years of age. Before taking Prazosin, you must notify your medical history with your physician. Inform them if you have conditions such as heart failure due to other heart issues, a history of fainting after urination, liver or kidney disease, or if you're scheduled for cataract eye surgery.

If you are pregnant, breastfeeding, suspect that you may be pregnant, or are planning to have a baby, it is important to seek advice from your doctor before taking this medicine.

Prazosin is often prescribed to be taken at bedtime to reduce the risk of dizziness and low blood pressure during the day. This drug can cause dizziness, especially when you first start taking it or if your dosage is adjusted. Be cautious when standing up from a sitting or lying position. Take your time to avoid falls.

1. Pfizer Limited, Electronic medicines compendium (EMC), [Revised on March 2023] [Accessed on 11th Sept 2023], https://www.medicines.org.uk/emc/files/pil.1068.pdf
2. Pfizer Labs, US Food and Drug Administration, [Revised on March 2009] [Accessed on 11th Sept 2023], https://www.accessdata.fda.gov/drugsatfda_docs/label/2009/017442s033lbl.pdf
3. Goodman & Gilman’s, The Pharmacological Basis of Therapeutics, Adrenergic agonists and antagonists, 12th edition, 2011, 305.
4. KD Tripathi, Essentials of Medical Pharmacology, Antiadrenergic drugs and drugs for glaucoma, 7th edition, 2013, 143.

The drug information on this page is not a substitute for medical advice; it is meant for educational purposes only. For further details, consult your doctor about your medical condition to know if you are eligible to receive this treatment.