A Burning Issue For Horses

The top-selling prescription drug for humans is now going to the farm: The government has approved the chemical in Prilosec to treat ulcers in horses.

Merial Limited, based in Iselin, New Jersey, will sell the horse drug under the brand name GastroGard. It's made of omeprazole, the active ingredient in the Prilosec that humans use to treat their own ulcers.

For horses, omeprazole is mixed into an oral paste.

Who knew horses got ulcers?

Actually, the seriousness of equine stomach ulcers is a fairly recent discovery, and Friday's approval by the Food and Drug Administration (FDA) provides veterinarians with their first treatment.

Gastric ulcers are a common problem in foals and in horses in stressful environments, particularly racehorses and other performance horses, the FDA said.

According to Merial, up to 1.8 million performance horses may have ulcers. The most noticeable symptoms are decreased appetite, colic, poor hair coat and poor body condition. In foals, symptoms also may include intermittent nursing.

In humans, stress does not cause ulcers - a bacterium called H. pylori is the main culprit.

Also, certain medications such as aspirin can cause ulcers by eroding the stomach lining.

Most human patients are treated with a combination of antibiotics to kill H. pylori and anti-acid drugs such as Prilosec that shut down gastric acid production so the stomach has time to heal.

But H. pylori hasn't been found in horses. Feeding practices, training and trailering, competing and even hospitalization seem to contribute to ulcer formation, Merial said.

Veterinarians tested GastroGard in 300 horses at 15 sites around the country. Used once a day for four weeks, it healed or reduced the severity of ulcers in 99 percent of treated horses, Merial said.

The FDA approved its use in foals older than 4 weeks and adult horses, by prescription only from a licensed veterinarian.

FDA warned there is no proof of the drug's safety in pregnant or lactating mares.