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Drug Details

  • Drug Name: Acepromazine
  • Common Name: Promace®, Aceproject®
  • Drug Type: Tranquilizer
  • Used For: Motion sickness, anxiety
  • Species: Dogs, Cats
  • Available Forms: 5mg, 10mg, and 25mg tablet, Injectable
  • FDA Approved: Yes

General Description


Acepromazine is the most common tranquilizer and central nervous system depressant given to pets. It is used to prevent anxiety associated with thunder, fireworks, vet or groomer visits, and other things your pet may fear. It is effective treatment against motion sickness and nausea associated with car or plane rides.


The effects typically last 6-8 hours. It is more effective to give this drug 45-60 minutes before your pet is expected to display any anxious behavior.


How It Works


How Acepromazine works is not well known. It is, however, suspected that it acts on the receptors in the brain for dopamine. Dopamine transmits emotion signals from cell to cell and by blocking these receptors, prevents pets from exhibiting extreme fear or anxiety.


Acepromazine also stabilizes the heart rhythm, lowers blood pressure, and acts on the brain to reduce your pet’s nausea.


Storage Information


Store in a tightly sealed container at room temperature.


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


Acepromazine may result in these side effects:


  • Increased seizures in epileptics
  • Exposure of your pet’s "third eyelid"
  • Low blood pressure
  • Change in respiratory rate
  • Heart failure
  • Aggression (especially in cats)
  • Constipation
  • Seizures
  • Convulsions
  • Vomiting
  • Shock
  • * Death

Acepromazine may react with these drugs:


  • Neomycin (and other aminoglycoside antibiotics)
  • Anesthesia
  • Antacids
  • Anticholinergics
  • Antidiarrheal drugs
  • Phenobarbital (and other barbituate drugs)
  • Diazepam (and other central nervous system depressants)
  • Clomipramine (and other tricyclin antidepressants)
  • Atropine sulfate
  • Epinephrine
  • Phenylpropanolamine
  • Phenytoin sodium
  • Propranolol
  • Quinidine




USE CAUTION WHEN ADMINISTERING THIS DRUG TO OLDER PETS - effects are often prolonged in older pets.

USE WITH CAUTION WHEN ADMINISTERING THIS DRUG TO GIANT BREED DOGS, ESPECIALLY THE BOXER AND SIGHTHOUND BREEDS - Giant breed dogs tend to be more sensitive to the drop in blood pressure experience by pets on this medication.


Some terrier breeds may be resistant to the effects of this drug.


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