How Long Does Ace Last in Horses? Understanding the Effects and Duration of Acepromazine

Ace is a popular drug commonly used to calm horses during veterinary procedures or when riders transport them. But, have you ever wondered how long does ace last in horses? If yes, then you have landed in the right place. Understanding the duration of this drug’s effect on horses is essential for administering the right dosage and ensuring the animal’s safety. In this article, we will delve into the details of this tranquilizer, exploring its benefits, dosage, and how long it lasts in horses.

Horse owners and veterinarians use ace as a sedative or pre-anesthetic medication to calm horses’s mind and ease their stress. This tranquilizer is a go-to solution in many situations, including medical examinations, transport, and surgeries. However, there is a limited time where you can safely use ace on horses to avoid risks. Administering an overdose to a horse can lead to severe consequences, including prolonged sedation, reduced mobility, and compromised respiration. Therefore, understanding how long does ace last in horses is an essential aspect of using the tranquilizer safely.

Knowing how long ace lasts in horses is vital for ensuring the optimized use of this vital tranquilizer. As you read on, you will learn how long the drug lasts and how to safeguard your horses against the overdose of this tranquilizer. So, buckle up, and let’s explore the exciting world of ace tranquilizer.

What is Ace and how does it work in horses?

Ace, or Acepromazine, is a tranquilizer commonly used in horses to help them relax and calm down. It is a medication that has been used for many years and is considered a safe and effective solution for managing a horse’s anxiety and stress levels. Ace can be used for a variety of reasons, including during transportation, for veterinary procedures or during shows or competitions.

  • Ace is a phenothiazine tranquilizer that works by blocking the dopamine receptors in the brain. Dopamine is a neurotransmitter that is responsible for regulating mood, emotions, and behavior. By blocking these receptors, Ace helps to reduce the horse’s anxiety and stress levels. It also has a sedative effect, which can help to calm the horse down and make it more manageable.
  • Ace is available in both oral and injectable forms. The injectable form is often preferred because it is faster-acting and provides a stronger effect. However, the oral form is easier to administer and may be a better option for horses that are difficult to handle or for owners that prefer not to use needles.
  • It is important to note that Ace is a controlled substance and should only be administered by a licensed veterinarian. It can only be prescribed for medical purposes and is not recommended for use as a long-term solution for behavioral issues. Overuse or misuse of Ace can lead to serious side effects, including hypotension, tremors, and even death.

If you are considering using Ace for your horse, it is important to discuss your options with your veterinarian. They can help you determine if Ace is the best solution for your horse’s needs and provide guidance on proper dosages and administration.

The legality of using Ace in horse competitions

Acepromazine, also known as “Ace,” is a sedative commonly used in veterinary medicine for horses. The medication is used to help calm horses during transportation, veterinary procedures, or other stressful events.

  • However, the use of Ace in horse competitions is strictly regulated and is not allowed without a veterinarian’s prescription.
  • Ace is a prohibited substance in horse racing and is included in the list of substances banned by the International Federation for Equestrian Sports (FEI).
  • The misuse of Ace can result in severe consequences, including fines and suspension of competition privileges.

Horse owners and trainers need to be aware of the legal requirements and regulations surrounding the use of Ace in competitions. It is vital to consult with a veterinarian before administering any medication to horses.

It is also crucial to understand the potential side effects of Ace, including hypotension, decreased respiratory rate, and decreased gastrointestinal motility.


The use of Ace in horse competitions is strictly regulated, and it is essential to follow all legal requirements and regulations. Horse owners and trainers need to consult with veterinarians and understand the potential side effects before administering any medication to horses. By following proper protocols, we can ensure the safety and health of our horses in competitions.

Pros Cons
Can help calm horses during transportation and veterinary procedures Misuse can result in severe consequences
Legal with a veterinarian’s prescription Prohibited substance in horse racing and included in the list of substances banned by the International Federation for Equestrian Sports (FEI)
Potential side effects, including hypotension, decreased respiratory rate, and decreased gastrointestinal motility

Ace can be a helpful medication for horses in certain situations, but it is crucial to use it properly and legally. By being aware of the potential risks and following legal regulations, we can ensure the safety and well-being of our horses.

Dosage recommendations for Ace in horses

Acepromazine, commonly known as Ace, is a sedative drug used in horses for various reasons. It is primarily used to sedate horses during veterinary procedures, such as dental work or diagnostic imaging. In this article, we will discuss the dosage recommendations for Ace in horses and what factors can impact the effectiveness of the drug.

  • The starting dosage for Ace should be 0.02 to 0.05 mg/kg, which is equivalent to 2 to 5 mg for every 100 pounds of body weight. This dosage can be adjusted based on the individual horse’s response to the drug.
  • Horses with certain medical conditions, such as liver or kidney disease, may require a lower dosage of Ace to avoid potential complications. It is important to consult with a veterinarian before administering Ace to a horse with a pre-existing medical condition.
  • The route of administration can also impact the dosage requirements. IV administration typically requires a lower dosage compared to IM or oral administration.

It is essential to consider the horse’s age, weight, and temperament before administering Ace. Younger horses may require a smaller dose compared to older horses due to their varying levels of sensitivity to the drug. Additionally, horses with a more reactive temperament may require a higher dose compared to those with a calmer disposition.

It is crucial not to exceed the recommended dosage of Ace, as it can lead to significant adverse effects, such as respiratory depression and hypotension. However, when administered correctly, Ace can efficiently sedate horses without compromising their physiological functions.

Mode of Administration Dosage Recommendation
IV 0.02 to 0.03 mg/kg
IM 0.03 to 0.04 mg/kg
Oral 0.1 to 0.2 mg/kg

In conclusion, Ace can be a useful drug for sedating horses during veterinary procedures. However, proper dosage recommendations must be followed to avoid any adverse effects. It is crucial to consult with a veterinarian before administering Ace to ensure the horse’s safety and comfort.

Potential Side Effects of Ace in Horses

Acepromazine, commonly known as Ace, is used in horses as a sedative and tranquilizer, but like many medications, it may cause certain side effects. These side effects range from minor to severe and may vary from one horse to another. Some of the potential side effects of Ace in horses are:

  • Drowsiness and lethargy: These are common side effects and are expected when using Ace in horses. Your horse may seem uninterested in food or water and may be unsteady on their feet.
  • Low blood pressure: Ace may cause a drop in blood pressure in some horses, which can lead to weakness, fainting, or collapse. It’s important to monitor your horse’s vital signs when administering this medication.
  • Respiratory depression: Ace can cause a decrease in the rate and depth of breathing in some horses. This can lead to difficulty breathing and may require immediate veterinary attention.

It’s important to note that these side effects are not always serious and may subside on their own. However, in some cases, they may require medical attention. Your veterinarian will be able to advise you on how to manage any side effects and when to seek veterinary care.

It’s also important to consider the potential for allergic reactions to Ace. Some horses may be hypersensitive to the medication and may experience anaphylaxis, a severe allergic reaction that can be life-threatening. Signs of anaphylaxis include difficulty breathing, swelling of the face or tongue, hives, and collapse. It is important to have epinephrine available to treat allergic reactions.

Side Effect Description
Drowsiness and lethargy Expected side effect, may make the horse uninterested in food or water, and unsteady on their feet.
Low blood pressure May cause weakness, fainting, or collapse. It’s important to monitor your horse’s vital signs.
Respiratory depression May cause difficulty breathing and may require immediate veterinary attention.

In conclusion, Ace is a widely used sedative and tranquilizer in horses, but it may cause potential side effects. Some of the common side effects include drowsiness, lethargy, and low blood pressure, while more severe side effects may include respiratory depression and allergic reactions. Always consult with your veterinarian before administering any medication to your horse and monitor them closely for any side effects.

Factors that can affect how long Ace lasts in horses

Acepromazine, commonly known as Ace, is a sedative that is used in equine medicine. It is a tranquilizer which is primarily given to horses for calming and relaxation purposes. Ace works by inhibiting the release of dopamine, a neurotransmitter that creates excitement and anxiety, to sedate the animal.

The effects of Ace can vary depending on the horse’s age, sex, size, and overall health. The duration of the effects depends on several factors, including the dosage administered, the route of administration, and the horse’s individual metabolism.

Factors affecting the duration of ace in horses

  • Dosage: The dosage administered to the horse determines the strength and the duration of the Ace’s effects. A higher dosage will last longer, while a lower dosage will wear off quickly.
  • Route of administration: The method of Ace administration can affect the time that horses will remain sedated. Administering Ace intravenously will result in a faster onset of action and longer duration of effect than when administered orally or intramuscularly.
  • Horse’s individual metabolism: Horses vary in terms of their metabolism, and thus, they will respond differently to Ace. The same dosage given to two different horses at the same time may produce different results.
  • Horse’s age: The age of the horse determines how efficiently it can metabolize Ace. Younger horses take longer to metabolize Ace than mature horses.
  • Horse’s overall health: Horses that are healthy and free from any underlying medical conditions will metabolize Ace more efficiently than those suffering from diseases or health problems.

Methods to minimize the side effects of Ace

While Ace is beneficial in reducing anxiety and fear in horses, it poses a few side effects, such as low blood pressure, respiratory depression, and hypothermia. To minimize these effects, horse owners should take the following precautions:

  • Administer a minimal dosage that is effective for the intended purpose.
  • Monitor the horse’s blood pressure and heart rate during the Ace administration and after to identify any irregularities.
  • Keep the horse in a quiet and calm environment to reduce the chances of injuries due to loss of coordination and balance.
  • Ensure that the horse is warm and dry to reduce the risks of hypothermia, which can occur when the horse’s temperature reduces during sedation.

The duration of Ace in horses

The table below shows the approximate time that sedation from Ace can last based on the route of administration and the dosage used.

Dosage (mg/kg) Method Duration of action (hours)
0.01-0.02 Intravenous 2-3
0.02-0.1 Intramuscular 3-4
0.25 Oral 6-8

It’s crucial to note that the duration of action may vary based on individual factors, making it essential to monitor the horse’s response continuously.

In conclusion, while Ace is an efficient sedative, how long it lasts in horses depends on several factors that influence the duration of its effects. Administering the appropriate dosage, monitoring the horse’s response to sedation, and minimizing the potential side effects are vital in ensuring that the horse’s safety and welfare are maintained.

How to Administer Ace to Horses Safely and Effectively

Acepromazine, commonly known as Ace, is a sedative drug used in horses to calm them down and relax their muscles. It is often administered to horses during veterinary procedures, transportation, or events such as shows or races. However, administering Ace to horses requires caution and knowledge to avoid negative side effects. Below are some guidelines on how to safely and effectively administer Ace to horses.

  • Consult with a veterinarian: Before administering Ace to a horse, it is crucial to consult with a veterinarian. The vet can examine the horse’s medical history and current health condition and determine if Ace is necessary and the correct dosage to administer.
  • Establish proper dosage: The dosage of Ace varies based on the weight and temperament of the horse. It is crucial to establish the correct dosage as too much Ace can cause severe side effects such as lowered blood pressure and respiratory distress.
  • Administer Ace in a controlled environment: Ace should be administered in a calm and controlled environment, away from noise and distractions. It is ideal to have an experienced handler hold the horse during administration to ensure safety.

Additionally, it is crucial to monitor the horse’s behavior during and after Ace administration to ensure that there are no adverse reactions. Below are some common side effects of Ace:

Side effect Description
Low blood pressure Ace reduces blood pressure, and if too much is administered, it can significantly lower blood pressure, leading to dizziness and fainting.
Reduced respiratory rate Ace reduces respiratory rate, and if too much is administered, it can lead to respiratory distress, particularly in horses with pre-existing respiratory problems.
Decreased body temperature Ace can cause a decrease in body temperature, which can be problematic in cold environments or with horses that are not accustomed to the weather.

To avoid these side effects, it is essential to follow the correct administration procedures, monitor the horse closely after administration, and seek veterinary attention immediately if any issues arise. Ace can be a useful tool for horse sedation when used correctly, safely, and effectively.

Alternatives to Ace for calming horses, such as herbal supplements or training techniques

Acepromazine, commonly referred to as Ace, is a sedative frequently used in horses to reduce anxiety and stress levels during veterinary procedures or transportation. However, the duration and strength of the drug can be unpredictable, leading to adverse effects such as excessive sedation, lowered blood pressure, and decreased heart rates. Hence, many horse owners are searching for alternative solutions that are safer, more reliable, and less invasive. Below we discuss some alternatives to Ace for calming horses.

  • Herbal supplements: Various types of herbs have been known to produce calming and soothing effects on horses, such as chamomile, passionflower, valerian root, and lavender. However, it’s essential to understand that different horses may react differently to these supplements, and their efficacy is not scientifically proven. Moreover, some herbs may interact with other medications, so it’s crucial to consult with a veterinarian before administering any herbal supplements.
  • Behavioral training: Another effective way to reduce anxiety levels in horses is through behavioral training, such as desensitizing them to potentially scary stimuli, teaching them relaxation techniques, and exposing them to positive reinforcement. By consistently practicing these methods, horses can learn to cope with stressful situations in a calm and controlled manner, without resorting to sedatives.
  • CBD products: Cannabidiol (CBD) is a natural compound derived from hemp plants that has gained popularity as a safe and effective calming aid for horses. CBD products are available in various forms, including oils, treats, and topicals, and they work by interacting with the body’s endocannabinoid system, which regulates mood, stress, and anxiety levels. CBD is non-psychoactive, meaning it won’t get horses or humans high, making it an ideal alternative to Ace.
  • Acupuncture: Acupuncture is a traditional Chinese medicine technique that involves inserting needles into specific points on the body to stimulate healing and restore balance. In horses, acupuncture has been found to reduce stress and anxiety levels by promoting the release of endorphins, which are natural painkillers and mood enhancers. Acupuncture may also increase blood flow and oxygenation, reducing the risk of injury and improving overall well-being.
  • Thundershirt: A Thundershirt is a breathable, snug-fitting garment that wraps around a horse’s body, applying gentle pressure that mimics a hug. The pressure can stimulate the release of calming hormones, such as oxytocin, and create a sense of security and comfort, reducing stress and anxiety levels. Thundershirts are easy to use, non-invasive, and can be reused multiple times, making them a cost-effective alternative to Ace.
  • Meditation and mindfulness: While it may seem unconventional, meditation and mindfulness practices have been shown to have a positive impact on horses’ mental health and well-being. By teaching horses to focus on their breathing, relax their muscles, and clear their minds of distracting thoughts, they can learn to control their emotions and reduce their stress levels. Meditation and mindfulness may be a valuable addition to behavioral training and other calming techniques, helping horses to develop a more resilient and adaptive mindset.
  • Environmental modifications: Finally, modifying a horse’s environment can also help to reduce anxiety and stress levels. For example, reducing noise levels, providing adequate ventilation and natural light, and offering access to pasture and forage can all contribute to a calmer and more relaxed state. Additionally, playing music or using aromatherapy with calming scents such as lavender can also provide a calming effect on horses.


There are many alternatives to Ace for calming horses, ranging from herbal supplements to behavioral training, acupuncture, CBD products, Thundershirts, and meditation. Horse owners should consult with their veterinarians to find the best solution that suits their horse’s individual needs and circumstances. Ultimately, reducing stress and anxiety levels in horses is crucial for their overall well-being, performance, and safety.

The Effectiveness of Ace Compared to Other Calming Methods for Horses

Calming supplements and medications have become increasingly popular in the equine world, with Acepromazine (Ace) being one of the most commonly used drugs. However, it’s important to not only understand how long Ace lasts in horses, but also how it compares to other calming methods available.

Acepromazine is a sedative that works by blocking dopamine receptors in the brain, leading to a decrease in anxiety and tension. Ace is a fast-acting medication and typically takes effect within 15 to 30 minutes of administration. Its effects can last anywhere from 4 to 8 hours, depending on the horse’s metabolism and dosage given.

  • Herbal Supplements: Many horse owners and trainers prefer to use natural supplements, such as chamomile, valerian root, and magnesium, to promote relaxation in their horses. While some studies have shown positive effects, the results can vary depending on the individual horse and dosage.
  • B-Vitamin Injections: Some horses benefit from the addition of B-vitamins, such as thiamine and niacin, to their diet or through injections. These vitamins have been linked to improved nerve function and can have a calming effect in some cases.
  • Acupuncture: Acupuncture is an alternative therapy that has been used to treat a variety of equine conditions, including anxiety. By manipulating certain points on the body, acupuncture can help balance the energy in the body and promote relaxation.

While different calming methods can work for different horses, it’s important to also consider the potential side effects and risks associated with each. Acepromazine can cause a drop in blood pressure, which can be dangerous for horses with heart conditions or low blood pressure. It’s also been associated with muscle tremors and difficulty standing in some horses.

Therefore, it’s crucial to always consult with a veterinarian to develop a personalized plan for promoting relaxation and reducing anxiety in your horse. With their guidance, you can determine the best method for your horse’s individual needs.

Method Effectiveness Duration Potential Side Effects
Acepromazine Fast-acting, effective sedation 4-8 hours Drop in blood pressure, muscle tremors, difficulty standing
Herbal Supplements Varies depending on the individual horse and dosage Varies depending on the supplement Potential allergic reactions, lack of regulation in supplement industry
B-Vitamin Injections Can have a calming effect Varies depending on dosage and individual horse None known
Acupuncture Can be effective for some horses Varies depending on individual horse and treatment plan None known

By understanding the effectiveness and potential risks associated with different calming methods, horse owners and trainers can make informed decisions when it comes to promoting relaxation in their horses.

How long does it take for Ace to take effect in horses?

Acepromazine, also known as Ace, is a sedative commonly used in horses to help them relax and calm down. It is often used for procedures that may cause anxiety or stress, such as veterinary exams or transportation. Knowing how long Ace takes to take effect is crucial for administering the medication properly and ensuring that the horse remains safe and comfortable during the procedure.

  • The onset of Ace usually occurs within 15-30 minutes after the injection is given. The horse may start to become lethargic and uncoordinated, which is a sign that the medication is beginning to take effect.
  • Peak sedation occurs after approximately 45-60 minutes. At this point, the horse will be significantly quieter and less reactive to stimuli such as noise or movement.
  • The effects of Ace can last anywhere from 2-6 hours, depending on the horse’s individual metabolism and the dosage given.

It is important to note that while Ace can be a useful tool for managing horse anxiety and stress, it is not a substitute for proper training and handling. In addition, some horses may have adverse reactions to Ace, such as increased sensitivity to noise or loss of balance, so it should only be used under the guidance of a veterinarian.

Overall, understanding the timing and effects of Ace is essential for proper administration and ensuring the safety and comfort of the horse during procedures that may cause anxiety or stress.


Source Title Link
Equimed Using Acepromazine in Horses
Michigan State University Acepromazine – A Review of its Use in the Horse

Ace Withdrawal Symptoms and How to Manage Them in Horses

While acepromazine or ace is commonly used in horses to calm them down during veterinary procedures, it is important to note that this medication can cause withdrawal symptoms. Withdrawal symptoms can vary in duration and severity depending on the dosage and the duration of use, among other factors. As a responsible horse owner, it is important to understand ace withdrawal symptoms and know how to manage them.

  • Anxiety: Horses may exhibit restlessness, nervousness, or increased blood pressure due to the rebound effect when the effect of the medication wears off. The horse may become more reactive and difficult to handle during this time.
  • Agitation: Horses may show signs of agitation and become more difficult to handle than usual.
  • Sensitivity to stimuli: Horses may become more sensitive to sounds, touch, or other external stimuli. This can cause them to become reactive and difficult to handle.
  • Appetite changes: Horses may experience changes in appetite, such as a decrease or increase in appetite.
  • Restlessness: Horses may become restless, unable to stand still, and may repeatedly shift their weight from one leg to another.

If a horse has been on ace for a prolonged period of time or at a high dose, the withdrawal symptoms may be more severe. To manage these symptoms, it is important to contact a veterinarian and follow their guidance. Below are some tips to help manage the symptoms:

  • Ensure a safe environment: It is important to ensure a safe environment for the horse during the withdrawal period. Remove any potential hazards and ensure the horse has ample space to move around.
  • Provide adequate nutrition: Horses may experience appetite changes during withdrawal, but it is important to provide them with adequate nutrition. Consult with a veterinarian on the best feeding practices during this period.
  • Keep the horse calm: Help the horse remain calm by minimizing external stimuli and providing consistent reassurance.
  • Monitor vital signs: Monitor the horse’s vital signs, including heart rate and breathing. If the symptoms persist or worsen, contact a veterinarian immediately.
  • Gradual weaning off the medication: Gradual weaning off the medication can help reduce the severity of the withdrawal symptoms. The veterinarian may adjust the dosage of the medication or recommend an alternative medication to help transition the horse off ace.
Symptom Duration
Anxiety Several days to a few weeks
Sensitivity to stimuli Several days to a few weeks
Agitation Several days to a few weeks
Appetite changes Several days to a few weeks
Restlessness Several days to a few weeks

Ace withdrawal symptoms can be uncomfortable and even dangerous for horses if not managed properly. By being aware of the symptoms and how to manage them, horse owners can ensure a safe and smooth transition off of acepromazine.

FAQs: How Long Does Ace Last in Horses?

Q: What is Ace and what is it used for in horses?
A: Ace is a sedative drug commonly used in horses for various reasons, including calming them down during veterinary procedures, transport, or training.

Q: How long does Ace last in horses?
A: The duration of Ace’s effects depends on several factors, including the horse’s size and weight, the dosage administered, and the route of administration. Generally speaking, Ace’s effects can last anywhere from 30 minutes to several hours.

Q: How is Ace administered to horses?
A: Ace can be given to horses orally, intravenously, or intramuscularly, depending on the veterinarian’s preference and the situation at hand. Injectable Ace usually takes effect more quickly than oral Ace.

Q: Can horses develop a tolerance to Ace?
A: Yes, like with any medication, horses can become desensitized to Ace’s effects if they are exposed to it frequently or in high doses. This can be dangerous and is not recommended.

Q: Are there any side effects or risks associated with Ace use in horses?
A: Yes, Ace can cause a range of side effects in horses, including a drop in blood pressure, slower heart rate, difficulty breathing, uncontrolled urination or defecation, and a loss of coordination. Overdose or misuse of Ace can even lead to coma or death.

Q: Can Ace show up on drug tests in horses?
A: Yes, Ace is a controlled substance and can be detected in blood or urine tests. It is important for horse owners and trainers to be aware of this and to follow legal and ethical guidelines for Ace use.

Q: Is Ace the only sedative drug available for horses?
A: No, there are other sedative drugs that can be used in horses, such as Xylazine or Detomidine. Each drug has its own benefits and drawbacks, and the veterinarian will choose the most appropriate one for each situation.

Closing Thoughts

Thank you for reading this article about how long does Ace last in horses. It is important to remember that sedative drugs like Ace should only be used under the guidance of a licensed veterinarian, and in compliance with legal and ethical standards. If you have any questions or concerns about Ace or any other aspect of horse healthcare, please consult with a professional. Don’t forget to check back for more informative articles and resources about equine care and management!