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What Should I Give My Horse To Calm It: Ace Or Dorm Gel?

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Horses may need a calmative supplement for various reasons. Horses have fears and anxiety issues that can put them and those working with them in danger. Standing still while the farrier or dentist does their job or being clipped maybe something a horse refuses to do due to past experiences or pain. 

Only some calming supplements work for some horses. Dorm gel has been most popular with horse owners due to the double effect of sedation and pain-relieving agents versus Ace, which is only a sedative. Dorm also comes in an easy-to-apply gel tube versus ace in tablet form for oral use.

Finding a calming supplement that aids your horse with anxiety and stress issues is vital for the horse’s safety, the people that work with the horse, and your sanity. In this article, I look at calming supplements, their benefits for your horse, and some alternatives.

Picture of a calm sorrel horse in training.

Below is an informative YouTube video on Dormosedan Gel.

Which is better to give your horse Dormosedan or Acepromazine?

It’s difficult to say whether Dormosedan or Acepromazine is a “better” sedative to use on horses, as the effectiveness of these medications can vary depending on the individual horse and the situation.

Dormosedan and Acepromazine are central nervous system depressants commonly used to sedate horses for procedures such as dental work, castration, and transportation. However, they have different mechanisms of action and can produce different effects in horses.

Dormosedan gel is an oral medication that is administered into a horse’s mouth. It is a relatively short-acting medication that can cause sedation within minutes of injection. However, it can also cause significant muscle relaxation.

Acepromazine, on the other hand, is typically given by injection. It is a longer-acting medication that may last several hours. Acepromazine is less likely to cause significant muscle relaxation or suppress pain in horses, but it may not be as effective at reducing anxiety or fear.

In general, it’s important to consult with a veterinarian before using either of these medications on your horse. Your veterinarian can help you determine the best medication and dose based on your horse’s needs and the specific situation.

We currently have a filly in training that is meaner than any horse I’ve ever been around. She pins her ears and kicks the stalls any time a stranger enters the barn. However, when you get on her back, she calms down and is easy to handle.

But there remains one problem, she loves to run hard all the time. If she continues this way, she will hurt herself. To relax her, I’ve found that giving her a little Ace does the trick. It calms her, but she retains focus and enjoys training.

I like using Ace better than Dorm Gel because it doesn’t mask the pain, so if she isn’t feeling good, she will display symptoms. On Dorm Gel, she is likely to keep running through an injury.

Here’s a look at Dormosedan and Acepromazine:

Dormosedan Gel (Dorm)

Detomidine is the active ingredient in Dormosedan Gel (Dorm). It is a popular paste that comes in an easy-to-apply tube with a nozzle to insert under the horse’s tongue. You need to get the placement of the gel right and ensure that it stays under the tongue for absorption to work effectively. If the gel is swallowed, it will have no effect.

Dorm gel provides a chemical standing restraint that also has strong pain-relieving properties. However, it can take twenty to forty minutes to work, depending on the dosage and size of the horse. For most horses, it takes forty minutes to be effective and typically lasts two hours.

I often hear it referred to as oral Ace. It is very easy and effective but expensive; for most application I prefer using Ace.

Acepromazine (Ace)

The active ingredient in (Ace) is Acepromazine maleate. It has a sedative-like function that acts as a muscle relaxant but does not contain any chemicals for pain relief. Some owners have reported that horses can still display explosive reactions under Ace. As a result, most farriers prefer not to work with horses medicated with Ace.

One of the main reasons owners and vets prefer not to use Ace or use it in minimal doses is the paralysis of a gelding or stallion’s penises. Primarily, Dorm and Ace are used as chemical standing restraints, and are not recommended to calm a horse down before riding.

Picture of a frightened horse with its ears pinned.

Benefits of using a calmative.

Apart from the obvious that your horse is easier to handle, posing less of a threat to himself and the people around him, there are other benefits to using calmative supplements.

Dormosedan and Acepromazine are used to sedate horses. They are central nervous system depressants that are commonly used for procedures such as dental work, castration, and transportation. Some of the potential benefits of using them include:

  • Reduction of anxiety and fear in horses, making them easier to handle and work with.
  • Sedation for procedures without causing significant muscle relaxation or loss of consciousness.
  • Reduce the risk of injury to both the horse and the handler during potentially stressful situations.

However, it’s important to note that these are powerful medications that should only be used under the guidance of a veterinarian. It’s also important to follow your veterinarian’s instructions carefully when using this medication, as improper use can lead to adverse effects and potentially harm your horse.

Here is a look at the benefits of various calmative supplements:

Reduces The Flight Or Fight Response

Calmative products with tryptophan compounds show that the horse’s production of adrenaline decreases, reducing the scare response of flight or fight. It’s great for those horses that tend to spook easily.

Attitude Adjustment

Shortages of magnesium can often lead to the misfiring of the nervous signal transmission making the horse appear nervous and edgy. The addition of magnesium in the horses lacking this in their diet can help repair and enhance muscle contraction and signal transmission, which will show in the adjustment of the horse’s behavior.

Enhances Focus And Memory

Having a relaxed and calm horse by reducing his hyperactivity allows them to focus more clearly on what is asked of him and allows for better memory retention.

  • It can help to reduce anxiety and fear in horses, making them easier to handle and work with.
  • It can allow horses to be sedated for procedures without causing significant muscle relaxation or loss of consciousness.
  • It can help to reduce the risk of injury to both the horse and the handler during potentially stressful situations.
Picture of an equine dentist working on a horse after giving it Ace.

How To Administer A Calmative Supplement

Calmative supplements can be given to a horse in different ways for a long-term effect or a quick solution.

Long-Term Supplements

Long-term supplements are added to the horse’s food daily in the form of pellets or powder. This is a slower process and takes a few days to work into the horse’s system before you start seeing its effects. Still, it continuously impacts the horse as long as it is supplemented with food.


Some come in the form of a paste, much like deworming pastes. Much like a syringe, you can find a paste or gel in a tube and a plunger with a dial to set the correct dosage according to the horse’s weight and the dosage you require.

Some products, like Dorm gel, need to be administered under the tongue to be absorbed, while others can be applied on the horse’s tongue to be swallowed.

This allows owners to safely dose their own horses. It usually takes about twenty to thirty minutes to start working. However, it can last up to four hours, depending on the dosage and the horse.

Calmative supplements in tablets can be crushed and added to horse food or made into a paste and squirted into the horse’s mouth.


Chemical products like Dorm and Ace can also be administered intravenously, which is injected directly into the horse’s vein or intramuscularly, injecting it into the neck muscles.

Intramuscular injections can take about twenty minutes to start working on the horse; this depends on the horse’s reaction to the sedative. Intravenous works within a few minutes as this gets directly into the bloodstream.

What Factors Might Influence How Well A Calmative Supplement Works For Your Horse

Applying the correct dosage recommended for the horse’s size and weight is vital to ensure that the calmative supplement works as intended. 

Horses on high starch and sugar diets tend to be more excitable, prone to spooking, and having more violent reactions to outside stimuli.

Changing the diet to high fiber and oils will aid in working with the calmative supplement instead of canceling the effects.

When using oral pastes or gels for a specific event, ensure that the horse is already in a relaxed state. For example, an excited horse may not take as quickly to the sedative. Allow the horse to relax in a quiet environment while the product takes effect. 

Picture of a bay horse calmly going out to train.

Alternatives To Calmative Supplements

While many products on the market claim to help horses with anxiety, some may not be safe. When you are not entirely convinced about the use of sedatives, you can look at other avenues before using a calmative supplement.


Re-evaluating your horse’s diet may result in a change in the horse’s attitude and energy levels. Replacing high starch and sugar diets with more fiber and high oil diets can aid in calming a hot horse.

Horses can also become agitated and have a bad attitude if hungry. They are natural grazers that eat little but often. Ensuring your horse has enough haylage in the stall during long periods of being stabled may calm the hungry beast.


Horses can become depressed and sour when they are expected to perform the same exercises and routine daily. On the other hand, changing the routine can give the horse a challenge.

Incorporate ground poles or small jumps for the dressage horse. Do some long-reining or lunging instead of riding, and add a casual trail ride to keep things exciting for the horse.

Increasing the exercise routine is also a good idea for horses that are too energetic. Suppose you feed your horse and keep it from burning off some steam with enough exercise. In that case, chances are your horse has the energy to bounce about like an energizer bunny.

Desensitization Techniques

When a horse is specifically averse to certain conditions or situations. Situations like injections, having the farriers, boxing, or having certain parts of them touched may benefit from desensitization techniques to help them overcome their fears.

Introducing Calming Supplements

When introducing a calming supplement into your horse’s diet, it’s essential to know why you need to calm the horse down. For example, horses may have anxiety triggers to specific events, like boxing, having their hooves trimmed, needle shy, competitions, or clipping.

Some of these triggers benefit from a once-off dose of calming supplements that can provide the horse with a sedative-like state that lowers the anxiety and stress in the horse for that specific event. Others may need a daily supplement that helps the horse cope with the daily stress and anxiety in its environment.

When looking to calm the hyper horse with a tendency for a bad attitude, there are some dietary supplements that be fed to them on a prolonged basis, mellowing out their spirited explosions.

That being said, not all horses are prone to an aggressive disposition. Their display of aggression may be caused by other underlying issues that need to be investigated. Some issues may include incorrectly fitting tack, teeth problems, and pain.


Some horses are predisposed to be high-strung and may benefit from calmative supplements to ease their stress and anxiety. Others need a dose of a sedative to help keep them and the people around them safe while specific actions are being performed on them. The preferred product, in this case by many owners, is Dorm gel.

However, finding out why your horse reacts as he does is essential to remedy the issue with the correct action. Also, trying out alternatives to calming supplements can be a fun and exciting way to bond better with your horse.


How long does Ace stay in a horse’s system?

There’s no definitive answer to this question since it will depend on a number of factors, such as the dosage of ace, the weight and health of the horse, and how fast the horse’s metabolism is. However, Ace is generally out of a horse’s system in 48 hours.

How much Ace Do I need to calm my horse?

The recommended dosage of Ace for calming a horse is 2-4 mg per 100 lbs weight. In some cases, a higher dosage may be needed. Consult your veterinarian if you’re unsure how much Ace to give your horse.