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Drug Details

  • Drug Name: Hydralazine
  • Common Name: Apresoline®
  • Drug Type: Arterial dilator
  • Used For: High blood pressure, Congestive heart failure
  • Species: Dogs, Cats
  • Administered: 10mg, 25mg, 50mg, and 100mg tablets, Injectable
  • How Dispensed: Prescription only
  • FDA Approved: No

General Description


Hydralazine is a drug that opens up the blood vessels, treating high blood pressure and assisting in the treatment of congestive heart failure.


How It Works


Hydralazine works by relaxing the smooth muscle in the blood vessels. Nerve signals cause calcium to be released, which contracts muscles. Without calcium, muscles are unable to contract and blood vessels are unable to constrict. When Hydralazine inhibits calcium movement, the blood vessels are forced to relax, lowering the pressure inside them.


Storage Information


Read the drug label for storage information.


Missed Dose?


Give the dose as soon as possible. If it is almost time for the next dose, skip the missed dose, and continue with the regular schedule. Do not give your pet two doses at once.


Side Effects and Drug Reactions


Hydralazine may result in these side effects:


  • Hypotension
  • Vomiting
  • Diarrhea
  • Lethargy
  • Conjunctivitis
  • Water or urinary retension
  • Constipation


Hydralazine may react with these drugs:


  • Antihypertension drugs
  • Beta blockers
  • Sympathomimetic
  • Digoxin
  • Furosemide




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