According to clinical and Para clinical studies, older or more time trained horses are more susceptible to make stomach ulcer. First clinical symptoms are loss of weight, low appetite and bad physical performances.

In order to establish a certain diagnosis, the veterinarian must perform an endoscopy of the horse stomach; the procedure requires a three meter long endoscope.

As forage feeders, horses secrete hydrochloric acid continuously in the wild and with few higher peaks in horse stables; as they usually graze 24 hours a day, the lack of food between meals in captivity can easily lead to ulcerations. The high amount of HCl in the stomach is believed to be causing ulcer.

While eating, salivary glands secrete bicarbonate-rich saliva which like food itself tends to tamponate the excess of acid. During the lack of food supplies acid levels increase again and harass the gastric mucous membrane produced by mucous glands for protection.

Best managerial solution is to allow the horses a 24 hours access to hay between grain meals. Depending on the season horses are fed in stables with meadow, Lucerne, long stick oat hay, or they are let free to pasture. In spite of the care-takers reservations, full-time access to hay did not disturb the horses? appetite for grains. This strategy has shown less clinical manifestations of gastric problems and less worries for the owner.

24 hours right to use hay in stables, has also proven a decrease of several problems in the behavior of horses in captivity.

Controlling the use of oral corticosteroids and non-steroidal anti-inflammatory drugs such as phenylbutazone might also be useful as they inhibit the formation of PGE in the stomach. Prostaglandins suppress the production of HCl, increase the blood flow in the mucous layer of the stomach and moderate the secretion of bicarbonate and mucus. Prostaglandins also have the assent to protect the stomach from any kind of physical or chemical aggression.

In first line therapy treatments aspire to reducing the secretion of hydrochloric acid and its effects. Lately only Omeprazole and Ranitidine are accepted by veterinarian associations in treating horses.


Both Omeprazole and Ranitidine are considered to be prohibited before horse racing because of their drug-like properties. Medical treatments containing the two substances may only be made under veterinarian supervision; treatment schedule must always be registered in the stable diary.