How to Treat Gastric Ulcers in Horses: Expert Tips for Relief

  • 20 May 2023
  • 10 min read
How to Treat Gastric Ulcers in Horses: Expert Tips for Relief

As a horse owner, you should be aware of the common problem of gastric ulcers affecting horses of any age. According to recent studies, more than 50 percent of show horses, 90 percent of racehorses, and non-performing horses, including foals, are affected by gastric/hindgut ulcers. It is essential to recognize the problem early and treat gastric ulcers in horses before it is converted to a severe form.


Gastric ulcer syndrome is a common issue that affects the health and performance of horses, causing discomfort, poor health, and performance, and can even lead to sudden death if left unmanaged. As an aware horse owner, you can use our knowledge of risk factors to minimize and treat gastric ulcers to keep horses healthy.

In this blog, we will focus on treating gastric ulcers in horses and the various methods and medications available to diagnose and help heal them.

What are Stomach or Gastric Ulcers in Horses?

All types of horses, including foals and adults, are prone to moderate stomach ulcers, which can convert to severe ulceration if left untreated. Earlier, it was commonly known as equine gastric ulcer syndrome or equine gastric ulcer disease.

Gastric ulcers are lesions or erosions that occur in the stomach lining. In horses, gastric ulcers are most commonly found in the squamous mucosa, the upper part of the stomach connected to the non-glandular stomach. The same type of lining does not protect the squamous mucosa as the lower portion of the stomach withstands the acidic environment of the digestive system. As a result, the squamous mucosa is more susceptible to damage from stomach acid, which can lead to ulcers.

Hindgut Ulcers- Common Problem of Equine Hindgut

Unlike gastric ulcers in the stomach, hindgut ulcers occur in the hindgut, the last portion of the horse's digestive system. The hindgut includes the cecum, colon, and rectum, and it's responsible for breaking down and absorbing nutrients from the horse's food.

Horses are hindgut fermenters, meaning the hindgut is a vital part of their digestive system. Hindgut ulcers occur when the protective mucosal lining of the hindgut is damaged, exposing the underlying sensitive tissue to digestive enzymes and stomach acid.

There are several reasons why hindgut ulcers can develop in horses. One of the most common reasons is a diet high in starch and low in fiber. Feeding horses large quantities of grain or sudden changes in feed can cause an imbalance in the gut's natural microbial population, leading to hindgut ulcers.

What Causes Gastric Ulcers in Horses?

The horse's stomach is relatively small and divided into epithelial and non-glandular sections.

Hydrochloric acid (HCl) is continuously produced by the glandular part of the horse's stomach to aid digestion. If the horse is not eating the feed, the acid builds up and can cause painful ulcers to develop. Horses are designed to graze lightly throughout the day in the pasture, but working or trained horses may be stabled and fed on the owner's terms. 

This more restricted access to food can cause new acid build-up in the stomach, leading to ulcers.

Let's broadly discuss several factors contributing to the development gastric ulcers and hindgut ulcers in horses. These include:

1. Diet of the Horse

An imbalanced diet is one of the primary causes of gastric ulcers in horses. Horses feeding large amounts of concentrate feeds, such as grains, without adequate roughage may be at a higher risk for developing ulcers. This is because concentrated feeds can cause acid production in the stomach, damaging the lining and leading to ulcers. Also, this excess concentration upsets the naturally balanced bacteria colony in the hindgut, which may lead to ulceration. 

2. Different Stressors in Horses

Stress is another common cause of gastric ulcers in horses. This is because stress can cause changes in the digestive system, making the stomach lining more vulnerable to damage from acid. Horses exposed to high-stress levels, such as those transported frequently or subjected to intense training or competition, may be more susceptible to ulcers.

3. Medications With NSAIDs and Corticosteroids

Non-steroidal anti-inflammatory drugs (NSAIDs) and corticosteroids can increase horses' risk of gastric ulcers. These medications may irritate the stomach lining and increase acid production, leading to ulcers.

Clinical Signs of Gastric Ulcers in Horses

  • Clinical signs of gastric ulcers in horses can be non-specific in most cases. It often becomes difficult to differentiate the stomach ulcer issue from other digestive system problems in horses. 
  • Here we mention the signs of ulcers common to most foals, and adult horses have already experienced the problem with the correct diagnosis.

Signs of Gastric Ulcers In Adult Horses

  • Attitude change: You can notice this prior sign as a horse owner. Your horse will start behaving relatively abnormally regarding touch reflexes, eating behavior, exercising, resistance to riding aids, and more. 
  • Poor appetite
  • Colic: A generalized abdominal pain associated with discomfort, inappetence, kicking at the belly, rolling on the ground, etc. 
  • Decreased performance: Race and performing horses face pain and discomfort, leading to poor performance.
  • Poor body condition: The horse's condition worsens if ulcers are left untreated. 
    Weight loss

Signs of Gastric Ulcers In Foals (or Young Horses) 

  • Intermittent colic: Usually, a foal suckle 30 times a day to acquire the nutrition through the mother's milk. Spasmodic colic may be seen after suckling or eating. 
  • Poor appetite
  • Poor body condition
  • Diarrhea
  • Teeth grinding
  • Excess salivation
  • Potbelly

Horse owners must address such signs in the horses. Gastric ulcers in horses can be a severe chronic condition if left untreated.

How to Diagnose Horse Suffering from Stomach Ulcers?

You can suspect your horse for stomach ulcers by noticing any combination of the signs mentioned above in the horse. You must refer to your veterinarian for a confirmatory diagnosis and effective treatment.  

Veterinarians use several diagnostic techniques to diagnose stomach ulcers in horses. These include:

1. Gastroscopy

Gastroscopy is the gold standard for diagnosing stomach ulcers in horses. This procedure involves passing an endoscope through the horse's nose and into the stomach to visualize the lining of the stomach. During gastroscopy, the veterinarian can examine the squamous mucosa and look for signs of ulceration.

2. Blood Testing

Blood testing can also be used to diagnose stomach ulcers in horses. Precisely, veterinarians may measure the horse's blood levels of gastrin protein. Elevated levels of gastrin can indicate the presence of ulcers in the stomach.

3. Fecal Testing

Fecal testing is another diagnostic technique that can diagnose stomach ulcers in horses. Specifically, veterinarians may test the horse's feces for the presence of gastric blood. The presence of gastric blood can indicate the presence of ulcers in the stomach.

How to Treat Gastric Ulcers in Horses?

  • Excess acid production through glands in the glandular stomach is the main reason behind ulcer development. According to the etiology, ulcer treatment revolves around decreasing the acid production in a horse'shorse's belly and enhancing the protective mechanisms in the stomach to take action against extra-produced acid.
  • Cimetidine and ranitidine are H2 blockers that block the signal for the acid-producing cell, but it is short-acting (1-2 hours). Comparatively, omeprazole stops acid production for longer (14 hours) by blocking acid pumps. As such, studies have shown proton pump inhibitors like omeprazole can prevent gastric ulcers in horses. Sucralfate, a cytoprotectant, protects the stomach lining by adhering to ulcerated mucosa.
  • The efficacy of gastric ulcer treatment in horses varies depending on the ulcer's severity. Treatment with medication includes the following categories:

1. Acid Inhibitors- For inhibiting excess acid production

  • Omeprazole falls in the category of proton pump inhibitors which work by inhibiting acid production and allowing the ulcers to heal. Omeprazole is typically administered orally in the form of a paste or tablet.
  • The use of omeprazole in treating gastric ulcers in horses is highly effective. Studies have demonstrated that omeprazole can heal ulcers in as little as 28 days. Omeprazole also has a relatively low risk of side effects when used correctly.
  • One potential downside of omeprazole is that it can be expensive. However, there are several generic forms of medication available that may be more affordable.
  • It's essential to note that while omeprazole can be an effective treatment for gastric ulcers in horses, it does not address the underlying causes. It's critical also to consider other treatment options, such as dietary changes and management practices, to help prevent the reoccurrence of ulcers in the future.

  2. Using H2 Blockers- To block histamine production

  • Histamine-2 receptor antagonists (H2 blockers) are another medication that can be used to treat ulcers in horses. These medications block the histamine-2 receptors in the stomach, reducing the amount of acid produced.
  • The two most commonly used H2 blockers in horses are ranitidine and cimetidine. Both medications can be administered orally or intravenously and are available in tablet or liquid form.

 3. Antacid- For neutralizing the excess acid produced

  • Antacids work by neutralizing the stomach acid, which helps reduce the irritation of the ulcerated tissue. Antacids are often used with other medications, such as omeprazole or ranitidine, to help manage the symptoms of gastric ulcers.
  • It's essential to work with a veterinarian to determine the appropriate dosage and duration of treatment for gastric ulcers. In addition, it's necessary to address any underlying causes that may have contributed to the development of the ulcer, such as dietary changes, stress, or management practices, to prevent recurrence.

How Long Do Gastric Ulcers Take to Heal in Horses?

The time it takes for gastric ulcers to heal in horses can vary depending on the severity of the ulceration and the chosen treatment plan. Mild ulcers may heal within a few weeks, while more severe ones may take several months to heal completely.

In general, treatment for gastric ulcers in horses is based on reducing the amount of acid in the stomach, promoting healing of the ulcerated tissue, and preventing the recurrence of ulcers. This can be achieved through medication (as discussed above), diet modification, and management changes.


Q1- What are the signs of gastric ulcers in horses?

Ans- You can observe signs like poor appetite, recurrent colic, decreased performance, poor body condition, rough hair coat, altered behavior, and more in your horse.

Q 2- What is the best treatment for gastric ulcers in horses?

Ans- Proton pump inhibitors (PPIs) like omeprazole works by inhibiting the proton pump responsible for acid production, which prevents further ulceration. 

Q 3- How long do gastric ulcers take to heal in horses?

Ans- Healing depends on the severity of gastric ulcers in horses. Omeprazole in treating gastric ulcers in horses is highly effective in healing ulcers in as little as 28 days.

Q 4- What are the signs of gastric ulcers in foals?

Ans- Signs of foal ulcers include decreased nursing, intermittent colic, poor body condition, diarrhea, pot belly, teeth grinding, etc. 


Gastric ulcers are common and severe ailments in horses that lowers their condition and performance. We explained what gastric ulcers are, how they are caused, and how to treat them in horses to improve the quality of their life.

Omeprazole, a medication under the proton pump inhibitors, is most widely used for treating stomach ulcers in horses. It works by inhibiting the proton pump responsible for excess acid production in the horse's stomach, leading to mucosal damage and ulceration.

Treatment begins with the correct diagnosis. Contact your nearest veterinarian for help regarding diagnosis and suggesting an effective line of treatment.

Dr Akanksha Agnihotri is another animal lover like you cum veterinarian by profession. She has earned her B.V.Sc & AH from COVS & AH, Jabalpur, India. She has a knack for befriending animals/pets and treating them compassionately. She believes...

Akanksha Agnihotri

Dr Akanksha Agnihotri is another animal lover like you cum veterinarian by profession. She has earned her B.V.Sc & AH from COVS & AH, Jabalpur, India. She has a knack for befriending animals/pets and treating them compassionately. She believes...