Bute, Colitis, and Ulcers

On a blazing Idaho day, the 4-year-old Arab gelding Khalil showed signs of colic. Owner Patty Katucki made an emergency call to the nearby Idaho Equine Veterinary Hospital in Nampa. Upon the veterinarian's arrival, he gave Khalil Banamine and tubed him. Since the horse's heart rate dropped from 60 to 48 in response to the Banamine, he seemed to be getting some relief.

Patty took Khalil to Idaho Equine for observation the next morning (Thursday) and left for an endurance ride with her other two horses. Liz Scott, DVM, took a fecal sample, did blood work, and started him on Carafate (a colitis treatment) after diagnosing right dorsal colitis--possibly from a sensitivity to non-steroidal anti-inflammatory medication (NSAID, such as Bute or Banamine). On Friday he got GastroGard (to help prevent gastric ulcers) and pentoxifylline (to improve blood flow for the colitis and speed healing). Since colitis often leads to laminitis, his feet were radiographed.

When Patty heard Khalil had elevated digital pulses in both feet and laminitis was threatening, she sped home. Since he couldn't have typical Bute or Banamine treatment (because of his diagnosed NSAID sensitivity), he got IV DMSO as an anti-inflammatory.

Two years before, Khalil had presented with colicky distress and dark, hard manure. The albumin count in his blood resulted in a diagnosis of right dorsal colitis, but he wasn't scoped for ulcers at that time. "I gave Khalil Bute as directed on a couple of occasions for various youthful incidents, but certainly don't feel that he fits the profile of a heavily buted horse," Patty noted.

By Monday, Khalil had responded to colitis and colic treatment, but he was still uncomfortable. Scott scoped him and found gastric ulcers. Tuesday he went home and was put on easily digestible Purina Equine Senior feed and hand-grazing, while still on GastroGard and Carafate. After a month, he was scoped again; he still had ulcers. Two weeks later, the ulcers were still present.

"I've been doing this for a long time, and I've never had gastric ulcers that haven't responded to omeprazole paste (GastroGard)," Scott said. So she called Frank Andrews, DVM, MS, at the University of Tennessee (UT) in Knoxville.

Andrews, professor and section chief of large animal medicine at the UT College of Veterinary Medicine, who researches equine gastroenterology, noted that roughly 40-93% of performance horses have gastric ulcers. There are many contributors; although NSAIDs are sometimes culpable, stomach anatomy, stress, diet, and exercise can also contribute. He suggested there might be a bacterial infection in the ulcers and recommended an antibiotic (trimethoprim sulfa, or SMZ-TMP). The results were dramatic--two weeks later, a scope showed no sign of ulcers or scarring.

The equine esophagus extends into the first one-third of the stomach, making horses susceptible to acid reflux disease. Naturally present bacteria can colonize in ulcers, and the stomach acid can keep them from healing. "We try to hit these things in the first treatment and get rid of the acid by using GastroGard--the purple pill for horses," he says. "When the ulcers don't heal, we use antibiotics to kill the bacteria and help the ulcer heal. Experiments in rats show that bacteria such as E. coli can prevent ulcers from healing."

Horses have excess stomach acid when kept in box stalls and fed on a schedule, Andrews said. (Khalil lives outdoors with other horses, eating free-choice grass hay.) Being idle, especially on an empty stomach, can contribute, as can temperament. (Khalil's not stressed, Patty says. He's far less reactive than her other two Arabs, and he was being lightly schooled.) He also said horses can develop ulcers very quickly, even within three to four days in racehorses.

Is there a relationship between colitis and ulcers? "Probably not," Andrews said. "Colitis is a different disease. Horses may have concurrent gastric ulcers, but right dorsal colitis is much more severe. Usually when we see gastric ulcers, we look for another disease, because ulcers are rarely primary. However, they can be."

Rarely fatal in adults, ulcers can kill foals and contribute to colic and diarrhea in young horses. They can heal on their own, but, "If you take horses out of training and turn them out to pasture, you would expect higher spontaneous healing rates," Andrews said. This seems to demonstrate that stress and exercise can prevent ulcer healing.

Giving Bute as needed is still permissible. According to Scott, there is no way to know in advance if a horse is sensitive to NSAIDs.

Khalil is back to his regular diet of grass hay with vitamin/ mineral supplements appropriate to his area. He got his last dose of GastroGard 11 weeks after going home, although he'll be on Neigh-lox (an ulcer preventive) for the rest of his life.

About the Author

Sally Eckhoff

Sally Eckhoff is a horse trainer/literary critic in upstate New York, and she has authored a book on working horses, mules, and oxen in the 21st Century.

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