• Common Uses: High blood pressure, Congestive heart failure, Spasm of the urethra
  • Species: Dogs and Cats
  • Therapeutic Class: Antihypertensives

General Drug Information and Indications:

Prazosin is prescribed for dogs and cats to manage high blood pressure, congestive heart failure, and urethral spasms. It operates by relaxing small blood vessels (vasodilation), facilitating improved blood circulation, reduced blood pressure, and decreased cardiac workload. Although prazosin helps control symptoms, it does not cure the underlying health issues.

Administration Instructions:

  • Dosage: Administer prazosin as directed by a veterinarian. If a dose is missed, administer as soon as possible without doubling the dose.
  • Feeding: Give with food to improve absorption and reduce stomach upset.
  • Handling: Wash hands after administering the medication to avoid accidental exposure.

Side Effects:

Discuss any side effects with a veterinarian immediately. Common side effects include:

  • Dizziness or fainting, particularly when the animal first stands.
  • Digestive issues such as vomiting, diarrhea, or constipation.


  • Safety: Store medication out of reach of children and do not administer to humans.
  • Legal: Use is restricted to prescription by a licensed veterinarian.
  • Health Concerns: Not suitable for animals with low blood pressure or severe kidney issues.

Drug Interactions:

Avoid using with other medications that lower blood pressure such as beta blockers, sildenafil, verapamil, and nifedipine. Clonidine may reduce the effectiveness of prazosin.

In Case of Overdose:

Animals: Contact a veterinarian or the A.S.P.C.A. Animal Poison Control Center at 888.426.4435.

Humans: Call the National Capital Poison Center at 800.222.1222.


Follow specific storage instructions on the medication label or from your pharmacist, as different forms of prazosin may have varied requirements.