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Horse Stomach
Click here to learn more about
your horse’s stomach.

Equine stomach ulcers are
more than a pain in the gut.

Stomach ulcers, also known as EGUS (an abbreviation for Equine Gastric Ulcer Syndrome), can:

  • Keep horses from performing their best
  • Cause lasting damage to the stomach lining
  • Even cause death1

EGUS is caused by excess acid that can eat through the stomach’s protective lining. Your horse’s stomach produces acid nonstop throughout the entire day and can produce up to 16 gallons of acidic fluid every 24 hours.2 In a constant grazing setting, a steady flow of acid is needed for digestion, and the roughage and saliva help neutralize the acid.3 As you add more grain to your horse’s diet, acid levels can increase3 — especially with the addition of stress factors, such as training, new surroundings or transporting.4 Fortunately, your veterinarian can help you prevent EGUS, as well as treat and heal existing ulcers.

Preventing EGUS

Wherever there is stress, there can be stomach ulcers. Your horse is sensitive and may experience stress when exposed to situations you would think of as normal. Simply transporting your horse to and from one horse show, feeding him twice a day and giving him light exercise could be enough to develop EGUS.5

More surprising, your horse can develop stomach ulcers in as little as 5 days.5

To see more of the most common stress factors that can lead to equine stomach ulcers, as well as learn more about tips to help prevent EGUS during periods of stress, click on the logo below.

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Treating EGUS

If you see common EGUS clinical signs — such as changes in eating and drinking behavior, changes in attitude (for the worse) or recurrent colic4 — share this information with your veterinarian as soon as possible. If your veterinarian diagnoses EGUS in your horse, you’ll want to respond quickly. This can help reduce the extent of damage caused by stomach ulcers.

For more clinical signs of EGUS and information about the only FDA-approved medication that can treat and heal stomach ulcers, click on the logo below.

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1Radostits OM, et al. Veterinary Medicine: A textbook of the diseases of cattle, horses, sheep, pigs and goats. Philadelphia: WB Saunders Co.; 2007:237-241.
2Kitchen DL, Merritt AM, Burrow JA. Histamine-induced gastric acid secretion in horses. AJVR 1998;59(10):1303-1306.
3Murray MJ. Overview of equine gastroduodenal ulceration. AAEP Proccedings 1997;43:382-387.
4Equine Gastric Ulcer Council. Recommendations for the diagnosis and treatment of Equine Gastric Ulcer Syndrome (EGUS). Equine Vet Educ 1999;11:262-272.
5McClure SR, Carithers DS, Gross SJ, Murray MJ. Gastric ulcer development in horses in a simulated show or training environment. J Am Vet Med Assoc 2005;227(5):775-777.

Important safety information:
ULCERGARD can be used in horses that weigh at least 600 pounds. Safety in pregnant mares has not been determined.

CAUTION — Safety of GASTROGARD in pregnant or lactating mares has not been determined.
For prescription information on GASTROGARD, click here.

®GASTROGARD and ULCERGARD are registered trademarks of the AstraZeneca Group of Companies.