Acepromazine maleate is a medication that is commonly used as a tranquilizer and sedative in veterinary medicine. It is a neuroleptic drug that is approved by the FDA and has low toxicity. Acepromazine for dogs is most commonly used as a pre-anesthetic drug to promote relaxation and calming prior to anesthesia.

Dog acepromazine works by depressing the central nervous system and causing sedation, muscular relaxation, and a reduction in spontaneous activity. It does not provide any pain relief, but it can be used to control agitated animals during vet visits, procedures, and grooming, as well as to manage stress, anxiety, and motion sickness.

Continue reading to learn more about why your veterinarian may prescribe acepromazine and its uses, doses, and potential adverse effects.

Key points for dog owners

  • Acepromazine is used commonly as a tranquilizer and sedative in dogs before anesthesia and surgery.
  • It works by depressing the central nervous system and causing sedation, muscular relaxation, and a reduction in spontaneous activity.
  • Acepromazine should only be used under the guidance of your veterinarian due to its potential side effects and risks.
  • Acepromazine can also be used for sedation on car rides and motion sickness treatment.

What is acepromazine?

Acepromazine is a medication for dogs that acts as a sedative and tranquilizer by blocking dopamine receptors in the brain. It is commonly used to provide mild sedation and chemical restraint. Additionally, it can be administered off-label to prevent vomiting and manage central nervous system (CNS) overstimulation caused by certain CNS stimulant drugs.

Acepromazine is available in both oral and injectable forms. The injectable form is often preferred for its reliability in achieving consistent sedation and can be administered intravenously or subcutaneously.

It is important to note that acepromazine should only be used under the supervision of your veterinarian. While it is generally considered safe, there are some potential side effects, including low blood pressure, decreased heart rate, and respiratory depression.

When acepromazine is administered to your dog, it takes effect within 30-60 minutes. The medication can last for several hours, depending on the dosage and your dog’s individual response. It is important to note that acepromazine does not provide pain relief, so it should not be used as a substitute for pain medication.

How acepromazine works

Acepromazine works by depressing the central nervous system, leading to sedation, muscular relaxation, and a reduction in spontaneous activity. This medication achieves its calming effects by blocking dopamine receptors in the brain.

Dopamine is a neurotransmitter that plays an important role in regulating movement, emotion, and motivation. By inhibiting dopamine, acepromazine helps reduce anxiety and stress, making it an effective treatment for dogs with anxiety disorders.

Uses of acepromazine in dogs

Acepromazine is a commonly prescribed medication for dogs that can be used for a variety of purposes. It is primarily used as a sedative or tranquilizer to help calm down dogs that are overly active or anxious.

Here are some of the most common uses of acepromazine in dogs:

Pre-anesthetic sedation

Acepromazine is often used as a pre-anesthetic medication before surgery. It can help calm dogs down and make them more relaxed before they are given anesthesia. Acepromazine can also help reduce the amount of anesthesia that is needed during surgery, which can help reduce the risk of complications. In veterinary medicine, acepromazine is administered under the guidance of veterinarians to ensure its safe and effective use as a pre-anesthetic.

General sedation to treat anxiety

Animal behaviorists and veterinarians do not typically recommend acepromazine for chronic anxiety or phobias such as storms or fireworks. However, it can still be beneficial in reducing stress before and after surgery or for dogs who are hospitalized.

Motion sickness and vomiting

Acepromazine can also be used to help prevent motion sickness in dogs. It works by reducing nausea and vomiting, which can be especially helpful for dogs that get car sick or experience motion sickness during air travel.

Acepromazine dosage for dogs

When it comes to administering acepromazine to dogs, it is imperative to follow the correct dosage from your veterinarian to ensure the safety and well-being of your dog. The dosage of acepromazine may vary depending on the dog's size and the desired level of sedation.

For oral administration, the typical dosage of acepromazine for dogs is 0.25 to 1 mg per pound of body weight. It is important to monitor your dog's response and behavior after administering acepromazine. The injectable doses are much lower for dogs.

It is very important to start at the low end of the dosage range and increase thereafter if needed. Rely on the guidance from your veterinarian.

The following table provides a general guideline for the oral dosage of acepromazine for dogs:

10 lbs: 2.5 - 10 mg

25 lbs: 6.25 - 25 mg

50 lbs: 12.5 - 50 mg

100 lbs: 25 - 100 mg

It is important to note that acepromazine should only be administered under the supervision of your veterinarian. Overdosing or incorrect administration could lead to serious side effects such as slowed breathing, slowed heart rate, unconsciousness, seizures, and death.

Overdose information

If you suspect that your dog has overdosed on acepromazine, it is essential to seek veterinary attention immediately. Overdoses of acepromazine can cause significant depression of the nervous system in dogs.

Symptoms of an overdose may include excessive sedation, lethargy, severe weakness, pale gums, incoordination, changes in pupil size, agitation, shallow breathing, collapse, and seizures.

In the event of an overdose, your veterinarian may administer activated charcoal to absorb the medication and provide supportive care. This may include intravenous fluids to maintain hydration and monitoring of vital signs to ensure your dog’s safety.

If you suspect an overdose or an adverse reaction, please contact your family or emergency veterinarian immediately.

Side effects and risks, including low blood pressure

Although acepromazine can effectively treat anxiety and fear in dogs, it is important to understand the potential side effects, and risks that come with its use. Some of the most common side effects include lethargy, increased noise sensitivity, and low blood pressure.

Interestingly, some dogs exhibit unexpected reactions such as hyperactivity, aggression, biting/chewing, and nervousness after taking acepromazine.

Additionally, monitoring body temperature is essential during treatment, particularly in extreme environmental conditions, to prevent hypothermia, especially when dogs are transported in cold environments.

In severe cases, the use of acepromazine can lead to cardiovascular collapse due to low blood pressure, which can be life-threatening. This is why it is important to always consult with your veterinarian before administering this medication to your dog.

Precautions and contraindications

Before administering acepromazine to your dog, it is important to consider the following precautions and contraindications:

  • Epilepsy and seizure disorders: Although there is no definitive data, acepromazine is thought to adjust the seizure threshold and should be avoided in dogs with seizure disorders such as epilepsy.
  • Heart disease: Acepromazine should not be used in dogs with significant heart disease or low blood pressure. It can cause a drop in blood pressure and slow down the heart rate, which can be dangerous for dogs with pre-existing heart conditions.
  • Pregnancy: Acepromazine should not be used in pregnant dogs, as it may cause birth defects or harm to the developing fetus.
  • MDR1: Dogs with the MDR1 gene mutation, such as Collies and Australian Shepherds, may be more sensitive to the effects of acepromazine and may require lower doses or alternative medications.
  • Debilitated animals: Acepromazine should not be used in debilitated animals, as it can further weaken their condition.
  • Young animals: Use acepromazine with caution in young animals, as they may have specific vulnerabilities to the medication's effects.

It is important to inform your veterinarian of any pre-existing medical conditions or medications your dog is taking before administering acepromazine. This includes vitamins, supplements, and herbal therapies. They may recommend alternative medications or adjust the dosage based on your dog’s individual needs.

Interactions with other drugs

When administering acepromazine to your dog, it is important to be aware of potential drug interactions. Here are some medications that may interact with acepromazine:

  • CNS depressants: If your dog is taking other drugs that depress the central nervous system such as barbiturates (phenobarbital), using them alongside acepromazine can have an additive effect. This means your dog may become overly sedated. Your vet will likely reduce the doses of these other medications if acepromazine is being used.
  • Propranolol: Combining acepromazine with propranolol, a medication often used to treat heart conditions, can lead to increased levels of both drugs in your dog's system. This can be risky, so consult your vet for proper dosing.
  • Anti-diarrhea medications: If your dog is taking over-the-counter antidiarrhoeal mixtures like kaolin/pectin or bismuth salicylate (Pepto Bismol), these could affect how well acepromazine is absorbed in the gastrointestinal tract. It might reduce the effectiveness of acepromazine when taken orally.
  • Antacids: Antacids may decrease the effectiveness of acepromazine. Therefore, it is recommended to avoid giving antacids within two hours of administering acepromazine.

It is important to always inform your veterinary team of any medications your dog is currently taking before administering acepromazine. This will help to ensure that there are no potential drug interactions that could harm your dog.

Veterinary guidance and considerations

If your veterinarian prescribes acepromazine for your dog, it is important to follow their guidance carefully. Acepromazine should be used with caution in pets with certain medical conditions, such as liver disease, heart disease, low blood volume, shock, low white blood cell numbers, and stress. Dogs with these conditions may require lower doses of acepromazine or alternative medications to ensure their safety.

Additionally, acepromazine should not be used in pets who have been exposed to certain toxic insecticides and flea collars containing organophosphate compounds. Always inform your veterinarian of any pre-existing medical conditions or medications your dog is taking before administering acepromazine. If you have any concerns or questions about acepromazine, it is always best to consult with your veterinarian to ensure the best care for your pet


Acepromazine is commonly used in dogs as a pre-anesthetic to provide sedation and calmness before procedures. Its sedative effects can also help dogs in stressful situations, like travel or vet visits. Follow your veterinarian’s instructions carefully for dosage and administration, and be aware of potential drug interactions or side effects. Always inform your vet about any medications your dog is taking before giving acepromazine, and monitor for any reactions.

If you have any questions, please contact your veterinarian.