Diarrhea is a fairly common problem with horses, so it is important that you learn about it if you own one or want to. 

While it might not seem like this is a major issue, it can quickly become one. This is often a sign of a more serious health issue that needs to be addressed immediately.

Causes of Diarrhea in Horses

There are numerous possible causes of diarrhea in horses that you should be aware of. Some of these things are fairly minor, while others are more serious.

1. Bacterial Infection

The most common explanation for diarrhea in horses is bacteria like salmonella. It is possible for a horse to have this bacterium of them without showing symptoms of any kind. This is usually the result something that your horse ingested. Salmonella and other types of bacteria can have a hugely negative impact on the overall health of these animals.

2. Parasites

A parasitic infection is another possible explanation for your horse’s diarrhea. There are lots of different types of parasites that horses can get. This is often the result of a horse drinking water that has been left to sit for too long. It is very important that you keep your horse’s drinking water fresh.

3. Viruses

It’s also possible that your horse has coronavirus, as it has been known to cause severe diarrhea in these animals. This virus can wreak havoc on the lining of your horse’s intestines. In fact, it doesn’t take very long at all for it to cause permanent damage.

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 4. Inflammatory Bowel Disease

Inflammatory bowel disease or IBS is a somewhat common condition among horses, and diarrhea is one of the most common symptoms.

doctor checks horse

5. Eating the Wrong Thing

If your horse eats something that it shouldn’t, they can get bad diarrhea. This is especially common with horses that eat sand. If their body cannot process what they have ingested, they will likely experience this symptom.


There are multiple tests that a veterinarian might run if your horse has diarrhea. These tests can help to reveal the larger problem that is causing this symptom.

Some of the tests a vet might run on your horse include:

  • Ultrasound: An ultrasound can be helpful if the intestines inside of your horse are thickened. This test can also show if their lymph nodes are enlarged, which is a sign of a bacterial infection.
  • Fecal smaple: Your vet might collect a fresh fecal sample from your horse to analyze it for various bacteria, such as salmonella.
  • Biopsy: A biopsy of your horse’s abdominal fluid might be performed in order to see if there is any abnormal cell growth, which could indicate cancer.
  • Blood tests: It is fairly standard for a veterinarian to run blood tests on a horse if they are exhibiting signs of illness.


While diarrhea can be a serious problem for your horse, there are fortunately a number of effective treatments. The specific treatment that is prescribed will depend on the root cause.

sick horse e1590249776287


If your horse has diarrhea due to a bacterial infection, your vet will likely want to administer IV antibiotics. There are numerous antibiotics that can be very effective at combating even the most serious of these infections.

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Sometimes all it takes to stop your horse’s diarrhea is proper hydration. There is a chance that your horse is not getting enough water to drink on a daily basis. This can really help with putting a stop to this symptom very quickly. If your horse has diarrhea and isn’t getting enough water, the problem will only get worse.

Your vet might decide to put your horse on IV fluids to rehydrate them. This could take a day or two, but it is usually quite effective. These fluids are packed with electrolytes, which these animals need to remain healthy.

Dietary Changes

It might be necessary to change your horse’s diet, if this is determined to be the cause of their diarrhea. It is possible that some of the food you are giving them each day is causing their digestive system to become agitated.


There are medications that you can give to your horse if it has irritable bowel syndrome. While this condition can be somewhat serious, there are plenty of medications that are very effective at combating it.

Preventing Diarrhea in Horses

There are certain things that you can do to prevent diarrhea in your horse, such as:

  • Replace their water: It is crucial that you change out your horse’s water on a daily basis so it doesn’t get a bacterial or parasitic infection.
  • Choose their foods carefully: You’ll also want to make a point of choosing your horse’s foods carefully. This can go a long way towards avoiding a lot of serious digestive problems.
  • Regular checkups: You should make a point of scheduling regular checkups for your house with a qualified veterinarian. It is a good idea to do this at least twice each year. This can help you catch a lot of things before they become serious.
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  • Diarrhea in horses is often caused by a bacterial infection, such as salmonella.
  • Certain parasites can also cause diarrhea in horses. This can occur when a horse drinks tainted water or eats sand.
  • A viral infection is another possible explanation for diarrhea in horses.
  • Irritable bowel syndrome is not uncommon in horses, and it can cause pretty severe diarrhea.
  • The proper antibiotics can usually stop diarrhea that is caused by a bacterial infection.
  • IV fluids can help put a stop to your horse’s diarrhea, especially if they are dehydrated.
  •  Make sure that you feed your horse fresh, high-quality roughage and other foods on a regular basis.
  • If your horse has irritable bowel syndrome, there are numerous medications that can help with managing the condition.
  • You should get your horse checked out by a vet at least once or twice each year. This can help with catching health problems before they get worse.
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Hi! I'm Anna and I´m a certified cynologist (KAU, ACW). Expert, blue cross volunteer, owner of Chinese crested kennel "Salvador Dali" and breedless friend called Fenya. "I can't imagine my life without dogs and I totally support the idea #AdoptDontShop".