Help: My Horse Has Impaction Colic—What to Do

One morning I went down to the stables to give my horse his breakfast and take him to his pasture for the day. When I looked over his stable door, he was lying down, stretched out, and he was full of sweat and covered in sawdust flakes from his bedding. It looked as if he had been rolling throughout the night.  

I rocked him onto his feet and took him to his pasture. His mucus membranes were off-color, and I noticed he was breathing faster than usual. When he was in his pasture, he tried to roll again. I called my veterinarian, who advised me to walk him in hand until she arrived. 

Once my vet arrived, she did a complete examination and diagnosed my horse with impaction colic. We treated him with a nasogastric tube filled with water, additional fluids, and electrolytes. 

While my horse slowly started grazing again, my vet explained that impaction colic is one of the most dangerous types of colic. She explained the risk factors that can increase the chances of impaction and how to minimize these risks. 

What is Impaction Colic? Impaction colic is an accumulation of feed that causes an obstruction or blockage in the intestinal tract. The accumulation of feed and resulting food obstruction is usually created by large or cumulative amounts of dry feed that gets stuck in the U-bends or pelvic flexures of the large colon found in the large intestine. 

Impaction colic is one of the most dangerous types of colic. It causes severe abdominal pain and needs immediate vet attention. The severity of the impaction will depend on the size of the blockage as well as the location.  

What Causes Impaction Colic in Horses?

Many environmental and horse care factors can cause impaction colic:

  • The horse may not be getting enough roughage 

It is important that a horse’s digestive system is constantly digesting small amounts of forage or roughage (called trickle feeding) around the clock, as this promotes a healthy digestive system. The amount of roughage your horse gets in a day will depend on their weight. Horses should typically get 2% – 3% of their body weight in roughage (as grass and hay) daily. 

Depending on workload or stabling needs, some horses may need more protein and feed concentrates. Horses that are stabled for most of the day will need an adlib amount of roughage in the stable as they cannot forage from their pasture all day. 

  •  Dehydration 

Dehydration is one of the biggest causes of impaction colic. When the horse is hydrated, their gut will have a reasonable moisture quality, and food can easily pass through the wet and slippery digestive tract. 

In a dehydrated horse, the gut itself is dehydrated and will no longer have that wetness, making it very difficult for food to pass through the digestive tract. When the gut is dry, food can get stuck in the large intestine’s tight U-bends, causing a blockage or impaction. 

  • Over-feeding 

A horse’s digestive system is designed to digest small amounts of food throughout the day. That is why you should feed your horse several small meals daily. A horse should not get more than 4,5 pounds of concentrated feed per meal.

If your horse needs 12 pounds of concentrated feed per day, split the meals up into breakfast, lunch, and dinner, with 4 pounds for each meal. By doing this, the digestive system has time to break down and digest the food. A horse’s stomach functions optimally when ¾ full, which is about 4 pounds of mass at a time. 

When the horse has eaten a large meal, it can easily create a blockage in the gut, leading to impaction. 

  • Limited movement 

Movement helps kick-start the digestive system and encourages food to pass through the digestive tract easily. Horses should enjoy turn-out time each day, even if it is just for a few hours a day. It is even more important during winter that your horse has time to move around outside the stable, as the risk of colic is even higher. 

Movement stimulates the horse’s circulation, which boosts hydration of the gut, preventing impaction. 

  • Change of feed 

Changing a horse’s food too quickly disturbs the hindgut digestion and puts the horse at a greater risk of colic. The new concentrated feed should gradually form part of their meals and diet. 

A great way to change food gradually is by decreasing 25% of the old food while adding 25% of the new food. Every day you reduce the old food and increase the new food until the horse eventually gets only the new feed. 

  • Worms

A heavy infestation of worms can cause impaction or obstruction in the intestines. Essentially, your horse must follow a good deworming program, and fecal matter can be regularly sent to your vet for an egg count, especially if your horse is in a large herd or travels a lot.  

Signs of Impaction Colic in a Horse

Be aware of colic symptoms—it could save your horse’s life. 

  • Reduced fecal output 

People often believe that since the horse has still passed a small amount of fecal matter, the horse doesn’t have colic. However, the horse’s intestines are long, and if the impaction or blockage is located closer to the stomach, it can cause some pre-colic stool to still pass through the digestive system. These droppings are from the food that passes through the gut before the blockage forms. 

The number of droppings may decrease or seem drier than usual, so take note of any recent fecal matter, as even color can indicate the problem.

  • Visible colic symptoms 

Colic symptoms such as rolling, lying down, kicking or biting at the belly, sweating, lip curling, and wide-legged stretching may present. If you notice the horse is rolling, it is a good idea to get the horse up and walk them in hand while you wait for the vet to arrive. If the horse is lying down and not rolling, you may leave the horse under supervision until the vet arrives. 

  • Temperature, pulse, and respiration (TPR)

It is essential to check your horse’s TPR. If their TPR is not in normal ranges, the horse could be in pain and will need vet assistance. The higher the pulse and respiration, the more pain the horse is experiencing. Normal TPR ranges are:

Temperature – 99–101°F 

Pulse – 28 to 40 beats per minute

Respiration – 8 to 16 breaths per minute

  • Mucus membranes’ color 

The horse’s mucus membranes (the gums and eyelids) should be a salmon-pink color. You need to contact the vet if the mucus membranes are pale (almost blue or yellow) or bright red. 

Red membranes indicate an excess of oxygen and thinning of the blood as the horse goes into shock. Blue membranes may indicate oxygen levels have dropped, and the horse could have a twisted gut. Yellow-colored membranes may hint that liver function is compromised and shock.

Risk Factors for Impaction Colic in Horses

There are many risk factors for impaction colic, and knowing them allows you to minimize risks to your horse:

1. Water Intake 

Dehydration plays a considerable role in impaction colic, and ensuring the horse is drinking enough water is essential. During colder days, a horse is less likely to drink enough water, so you must ensure water buckets have not frozen over. 

Fill your horse’s water bucket with lukewarm water to encourage the horse to drink. Add salt to their diet for additional selenium and chloride, encouraging the horse to drink more water. The salt triggers the thirst response, leading to better hydration through natural drinking. 

During the hot days, it is a good idea to add electrolytes to their water or feed as this will help replace any minerals lost through sweating. Remember, when adding electrolytes to the water bucket, always ensure the second bucket of plain water is close by. 

2. Immobility 

A horse should enjoy the freedom of movement and move around as much as possible. Box rest is a serious risk factor for impaction colic, as the horse cannot move around as much as needed. If possible, take the horse for a short walk 2 – 3 times daily. The extra movement will mobilize the digestive system. 

Turn your horses out as much as possible. Yes, even in the cold winter months!

3. Over-Feeding 

When a horse is fed too much as one meal, the food is not digested as effectively as when you feed small amounts throughout the day. A horse’s digestive system is for the digestion of small amounts of feed, not large meals. In nature, horses will graze a little at a time for most of the day and night, never overfilling their stomachs.

Over-feeding can be a problem in winter because owners increase the concentrated feed to ensure their horses have enough energy to keep themselves warm. In some cases, like an older horse that loses condition in winter, increasing the concentrated feed can help the horse maintain a healthy weight. 

Instead of increasing the horse’s concentrated feed, increase their roughage and forage time, as this is where the horse gets the necessary nutrients, energy, and protein. With constant grazing and hay, horses can maintain weight and keep themselves warm.

4. Age-Related Dental Issues 

The first step in digestion is chewing, so if your older horse has any dental issues preventing the horse from chewing correctly, it could lead to swallowing unchewed food. Large food particles or bits constitute a significant risk for impaction colic as the food mass will be too big to pass down the digestive tract and get stuck in the U-bends of the large colon. 

Preventing Impaction Colic in Your Horse

As we all know, prevention is better than cure. Here are a few steps you can take to prevent impaction colic from happening to your horse: 

  • Access to clean, fresh water every day 

Your horse should be drinking 10 – 15 gallons of water every day and more on hotter days or after the horse has done strenuous exercise. Your horse should be getting a teaspoon of salt added to their concentrated food, as this will encourage the horse to drink. 

  • Good quality feedstuffs 

Remember that most of your horse’s diet will be hay and forage. Your horse must get high-quality hay and forage as this will help the digestion of food. Low-quality hay can be stalky and dry, making the hay harder to chew and break down and digest. 

  • Dentistry 

You should have an equine dentist examining your horse’s teeth with appropriate treatment every 6 – 12 months to avoid any severe dental issues that could affect the way the horse eats. Poor molar contact can lead to poor mastication of the feed, which leads to further complications. 

  • Exercise/movement 

Turn your horse out in the pasture every day. If you cannot turn your horse out, think about walking your horse for 30 minutes 3 times a day. 

Continue to exercise your horse regularly, which also goes for your retired horse. As they get older, they need more stimulation from movement through their gut. 

Treatment Protocol for Horses With Impaction Colic

Treatment may vary depending on the severity of the impaction:  

1. Walk The Horse 

Walking the horse is vital when it comes to colic. Walking the horse in hand at regular intervals can stimulate movement inside the gut. Do not allow the horse to roll; walk the horse again if they continuously try to roll. 

2. A Full Physical and Rectal examination 

Your veterinarian will do a complete physical and rectal examination. A rectal exam involves investigating the pelvic floor to diagnose impaction colic within the pelvic flexure or U-bends of the large colon. 

3. Gastric Tubing 

Once the vet has diagnosed colic, they will do nasogastric intubation or stomach tubing. This is when the vet passes a narrow tube up the horse’s nose, down the oesophagus, and into the stomach. 

The vet will put a large volume of water, laxatives, and electrolytes through the tube to help soften the impaction and rehydrate the gut and the horse. Most times, this is enough to loosen the impaction and bring relief.

4. Pain Relief 

The vet will often give the horse an anti-inflammatory drug such as Flunixin meglumine or meloxicam to help with pain and discomfort in the horse’s abdominal area. Injecting buscopan may also help relieve cramping and discomfort. 

5. Withhold Food 

The vet may recommend that you withhold your horse’s concentrated feed until the impaction has passed. Withholding sweet feed will prevent a further accumulation of food. Oftentimes, your horse may only get a handful of sweetened roughage throughout the day. Pelleted feed is not allowed while in recovery.

6. IV Fluids 

The vet may also give your horse IV fluids through an injection or drip, depending on the severity of the colic. IV fluids will help rehydrate the horse and limit any further fluid loss. 

7. Hospitalization 

Hospitalization is generally only for severe impaction colic cases where your horse may need multiple intravenous fluid injections, repeated stomach tubing, or surgery. 

Your Horse After Impaction Colic—Important Questions

It would be best if you managed what your horse eats and does after impaction colic. If you manage the horse correctly, the horse will have a much better recovery rate and prognosis. 

1. Can I feed their regular concentrate if my horse has just had an impaction colic? 

A horse suffering from impaction colic should not be fed any grain-based feed until the impaction has been resolved. After the impaction has resolved, you may offer your horse a few slices of hay or some fresh grass every couple of hours for two days. Over the next seven days, you can gradually give your horse smaller meals of their concentrated feed. 

Do not give your horse the whole meal all at once, and their stomach lining is sensitive, and large feed quantities may cause another colic episode. 

2. Should I walk my horse when they have impaction colic?

In cases where the horse is rolling, I recommend getting the horse up and encouraging the horse to walk in hand. Walking will revitalize gut mobility and prevent any injury from rolling uncontrollably. 

Take the horse for a brisk walk for 40 minutes but do not exhaust the horse. It is important to walk and intersperse this with a few opportunities for the horse to stand and rest. If the horse tries to roll again, continue walking. 

3. How long after my horse shows signs of impaction colic will it clear? 

The rate at which impaction clears will depend on the severity of the impaction. If you immediately notice the colic symptoms and call for vet intervention, the impaction can resolve within 24 hours. In bad cases of impaction colic, it could take 2 – 3 days for impaction to resolve. 

4. How soon after my horse has impaction colic can I ride them?

In a best-case scenario, where the impaction could be fully cleared within a day, you can ride 48 hours after the episode. I recommend light riding work as the gut lining can still be sensitive and gradually increase their work over the next few days. 

Movement is always essential during or after impaction colic, so even if you feel you should not ride yet, you can take the horse for a brisk walk in hand. 

5. What damage can a horse suffer due to impaction colic? 

A horse can suffer a lot of internal and external damage with impaction colic. When rolling violently or uncontrollably, the horse can cast itself in the stable (get stuck and be unable to get up) or get caught near a fence and possibly cause significant lacerations to their bodies. 

Violently rolling can also cause internal damage, such as a twisted gut, which is very dangerous. The horse will need surgery for the untwisting of the gut, but colic surgery has a low survival rate, especially if the impaction and twisted gut are severely compromised. Impaction colic can also cause gut sensitivity and ulcers. 


Managing the impaction risk factors can increase the chances of your horse living a full, happy life with a limited risk of impaction colic. Impaction colic is dangerous and claims the lives of so many horses. Contact your vet immediately when you observe the first signs of colic. 

By acting swiftly, I could save my horse’s life and prevent this from happening to my other horses. Colic can be a horse owner’s worst nightmare, but if you take preventive steps and minimize any risk factors, you can worry less about colic and help your horse to live a happy and safe life. If you’d like to learn more about horses’ yawning, why not read my guide on the reasons horses yawn and what it could mean

My Favorite Equine Resources For Horses and Donkeys

This list contains affiliate products. Affiliate products do not cost more but helps to support BestFarmAnimals and our goal to provide farm animal owners with accurate and helpful information.

Squeaky Chicken Toy is hilarious to watch and the horses love it! It’s not super tough so keep it away from dogs.

Dewormer with Ivermectin: I use this for my horses and my goats. Duvet makes a great dewormer. I switch between the Ivermectin one and one like this one so the worms don’t get immune to it.

Manna Pro Apple Flavored Nuggets are a delicious smelling treat that my horses go crazy over.

Equinity Amino Acid Supplement for Horses makes a big difference for any horse that’s struggling with arthritis, hoof issues, or just generally. It’s great for older horses who can’t absorb all the nutrients in their food as well!

Manna Pro Weight Accelerator helps older horses gain weight and stay healthier! This was especially helpful when one of my older horses lost weight over the winter and helped her regain her weight over the summer!

Farnam Fly Control goes on the horse or donkey and will keep the flies off your sweet pet. It makes horses way more comfortable and will keep sores from getting infected as well.

Wound Kote protects sores and wounds. It acts as an antiseptic and helps wounds heal faster. It works on both my horses and goats.

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