Merial, a Merck and Rhone-Poulenc company, announced today that it has received clearance from the U.S. Food and Drug Administration (FDA) to market Gastroguard (omeprazole) Paste, the first and only prescription medication approved by the FDA to heal and prevent the recurrence of stomach ulcers in horses. Omeprazole is the same active ingredient found in Prilosec the world’s leading anti-ulcer medication for humans.

“Only recently, with advances in diagnostic testing, has the seriousness of Equine Gastric Ulcer Syndrome (EGUS) been understood and until now, there was no approved medicine specifically designed for treating ulcers in horses,” said Dr. Frank Andrews, associate professor and section chief, Large Animal Medicine, University of Tennessee College of Veterinary Medicine, Knoxville, Tenn. “Gastroguard is an important new drug because it is the first medication that has been proven to heal stomach ulcers and, just as significantly, can prevent them from recurring even while the horse is still in training. This drug will have a significant impact on the equine industry.”

Gastroguard was granted accelerated review by the FDA because the molecule was new to veterinary medicine and had potential therapeutic value for an important, often serious condition. EGUS may affect as many as 1.8 million U.S. performance horses. Recent studies have shown that EGUS affects up to 93 percent of racehorses, almost 60 percent of other performance horses and up to 57 percent of foals (horses under the age of one year). Gastroguard will be available from veterinarians in two weeks.

Like People, Horses Get Ulcers, Too
As with human ulcers, stomach acid appears to be the main cause of horse ulcers. Excess acid can eat through the protective lining and damage the stomach. Among the most noticeable signs of ulcers are decreased appetite, colic, poor hair coat, poor body condition and poor performance. In foals, clinical signs may include grinding of teeth, colic, intermittent nursing, decreased appetite and weakness