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Kansas State University

Gastric ulcers in Horses


Gastric ulcers have been described in people, swine, cattle, small animals, and horses, and they were first recognized in horses in the 1960’s. The clinical signs associated with this disease include depression, abdominal pain, teeth grinding, drooling, and a tendency to lie for long periods of time. In adult horses, gastric ulcers usually present as chronic recurrent colic, acute colic, poor body condition, loss of appetite, and/or soft feces. In foals, however, the signs can be much more severe.

The factors predisposing horses to the build-up of stomach acid that causes ulcers are stress, long periods of time without food, and the extended use or use of large amounts of non-steroidal anti-inflammatory drugs such as phenylbutazone (bute) or flunixin meglumine (banamine) to control pain. The use of these anti-inflammatory drugs can cause ulceration not only in the esophagus and stomach, but also in the colon.

Who is at risk?

• All horses that are under pressure due to competitions, dressage, and racing are at a risk.
• Horses that are fed on a twice daily schedule with long periods time with no access to food.

Gastric ulcers are suspected in horses with clinical signs such as depression, weight loss, poor performance and mild colic after eating. The degree and severity of ulceration are determined by visualizing the stomach via gastroscopy.

                                 A                                                B                                             C 

Panel A represents a foal with gastric ulcers showing the clinical signs of drooling (arrow) and teeth grinding. Panel B and C represent a gastroscopy photograph of bleeding gastric ulcers in a horse.

Although the treatment may vary depending on the severity of the ulcers and their location, therapy is aimed at controlling the pain and lowering the levels of gastric acid. This is typically achieved by putting horses on oral medication to coat the ulcers (mucosal protectants) and medication to heal the ulcers. Depending on response to treatment, 14-28 days of medication are typically required for healing. Most ulcers will be gone at 28 days, but some may require longer therapy.
It may seem tempting to treat your horses at home with Pepcid®, Tums®, Pepto-Bismol®, Maalox® or other similar antacids sold for humans. The amount necessary to treat a horse with any of these substances would be monumental and would not control the pain nor heal the ulcers. Additionally, having to give repeated doses of these types of medication require a lot of time and restraint and may sour your relationship with your horse and cause him or her to resist treatment.

How can I avoid ulcers?

  • Feed your horse smaller meals throughout the day

  • Increase the levels of good quality roughage, free choice good quality grass hay is ideal.

  • Allow your horse to graze

  • Before treating your horse with banamine or bute for colic or lameness, discuss dosing amounts and frequencies with your veterinarian. If these drugs need to be given over a long period of time, supplementing the feed with half a cup to one cup of vegetable oil may protect the colon from ulcers.