Understanding Acepromazine Use in Dogs
Acepromazine is a prescription medication that's widely recognized in veterinary medicine for its sedative and tranquilizing effects on dogs. If your vet has mentioned acepromazine for your pet, you might be wondering exactly what it does, when it's appropriate, and what you should watch out for.
What Is Acepromazine?
Acepromazine is available both as tablets (typically 10 mg or 25 mg) and as an injectable solution. It's not a pain reliever but works by depressing your dog's central nervous system. This leads to sedation, muscle relaxation, and less spontaneous activity. The drug also has anti-nausea (anti-emetic) properties and can help stabilize heart rhythm in some cases.
Primary Uses of Acepromazine in Dogs
- As a tranquilizer for minor veterinary procedures, grooming sessions, x-rays, or travel.
- As a pre-anesthetic agent, reducing the amount of anesthesia needed during surgery for dogs (and sometimes cats or horses).
- To help control nausea and vomiting, especially related to travel (motion sickness).
Sometimes acepromazine is prescribed to manage urinary blockages (mainly in cats) or to alleviate itching from skin irritation. However, its main role in dogs remains sedation and reducing anxiety-like behaviors before stressful events.
How Is It Given?
You should give acepromazine about 30–60 minutes before you want it to take effect—such as before a car ride or vet visit. Tablets can be given with or without food. The effects usually last between four and eight hours but may persist up to 24 hours in pets with liver or kidney issues. Dosage always depends on your dog's weight, the situation at hand, and how they respond individually—so follow your veterinarian's instructions closely.
Precautions & Special Considerations
- Avoid use in pets with significant heart disease, low blood pressure, severe dehydration, shock, or liver disease.
- If your dog has allergies to phenothiazines (the drug family including acepromazine) or has had adverse reactions previously, don't use it.
- Pups exposed to organophosphate insecticides (like certain flea collars) shouldn't receive acepromazine due to increased toxicity risks.
Certain breeds are more sensitive: brachycephalic breeds (Boxers, Pugs), sighthounds (Greyhounds, Whippets), giant breeds, Collies, Shelties, Australian Shepherds, Shetland Sheepdogs—especially those with the MDR1 gene mutation—may need lower doses. Geriatric pets or those very young/pregnant/debilitated might also require adjustments. Baseline bloodwork may be recommended if your dog has underlying health concerns.
Acepromazine isn't generally recommended for aggressive animals unless under strict veterinary supervision; it could worsen aggression or noise sensitivity. There's also debate about using it for anxiety or phobias: while it reduces movement, it doesn't actually relieve anxiety—and may even make psychological distress worse. For these issues, vets often prefer other medications.
Drug Interactions
This medication can interact with many others:
- Sedatives/anesthetics/opioids
- Certain heart medications (e.g., quinidine)
- Antacids/antidiarrheals (kaolin/pectin/bismuth subsalicylate)
- Metoclopramide/cisapride/metronidazole/ondansetron
- Acetaminophen/NSAIDs/phenobarbital/fluoxetine
If your dog takes supplements or herbal products—or uses topical insecticides—always inform your vet before starting acepromazine.
Side Effects: What Should You Watch For?
- Sedation/drowsiness/depression
- Lack of coordination/weakness
- Lowered blood pressure/slower heart rate/decreased breathing rate
- Protrusion of the third eyelid (harmless)
- (Rarely) aggression/hyperactivity/restlessness
You might also notice discolored urine (pink/red-brown), decreased tear production (especially in cats), temperature regulation issues (risk of hypothermia/hyperthermia), pale gums, constipation, pain/swelling at injection sites if injected—and rarely allergic reactions like facial swelling or hives. If you see severe lethargy, collapse, seizures, signs of shock—contact your vet right away.
The MDR1 Gene Mutation & Breed Sensitivity
Certain breeds—especially Collies and other herding types—may have the MDR1 gene mutation that makes them more sensitive to acepromazine's effects. Lower doses are usually required. Your veterinarian may suggest a DNA test if you're unsure about your dog's genetic risk.
If You Miss a Dose or Suspect Overdose
- If you miss a dose: Give it when you remember unless it's almost time for the next dose; don't double up.
- If overdose occurs: Symptoms include excessive sedation/collapse/shallow breathing/severe weakness/pupil changes/agitation/seizures. Get veterinary help immediately.
Storage & Safety Tips
- Store tablets at room temperature (68–77°F/20–25°C), away from light/moisture; keep tightly closed and out of reach of children/pets.
- Acepromazine isn't intended for human use; accidental ingestion requires immediate medical attention.
Your Vet's Role & Monitoring
Your veterinarian may recommend monitoring heart rate/rhythm/blood pressure/temperature during repeated use or if your pet is on other medications. Always follow their guidance closely—they'll tailor dosing and precautions based on your dog's unique needs.
