Ask the Vet: Colic

Answered by Jean-Yin Tan, DVM, Syracuse Equine Veterinary Specialists, Manlius, NY

Question: My horse has a hoof abscess and has been on bute for a month. Do I need to treat for ulcers? 

Answer: The stressful event and any change in routine brought about by the foot abscess, combined with the use of the non-steroidal anti-inflammatory phenylbutazone, are all predisposing factors for gastric ulcers. Ideally, if the changes can be predicted, a horse should be started on 1mg/kg of omeprazole paste (Merial Gastrogard in the U.S.) beginning 3-5 days prior to the change, to prevent the formation of gastric ulcers. Since you are already a month into treatment, your horse likely has either developed gastric ulcers, or is not going to develop them. Before instituting treatment for possible gastric ulcers, I would recommend a discussion with your veterinarian on any changes you may have noticed to his weight and condition, appetite, and any signs of discomfort that can be associated with ulcers. His age, breed, and personality can also be factors that relate to his risk of gastric ulcers. Definitive diagnosis to determine if he does need to be treated would be achieved through a gastroscopy.

Question: I have a 32-year-old warmblood with a history of serious ulcers (before retiring.) He was treated with GastroGuard initially and again when he seemed to have trouble again due to being fed inadequately 12 hrs apart. His diet is now excellent and he is holding weight beautifully. He even has his top line back. He is given omeoprazole powder with his food. Is there any point to that powder? Once the ulcers are treated with Gastroguard, is that all that is necessary?

Answer: First of all, congratulations on successful treatment of his ulcers and getting him to an ideal weight! These are all indications that the initial ulcers have healed. However, having suffered from ulcers twice, I would agree that he is predisposed to developing ulcers and should be kept on whatever preventive strategies are possible.

As you mentioned, feeding practices and management are of paramount importance when aiming to prevent gastric ulcers. I would not only recommend small frequent feedings, but recommend that his forage be primarily alfalfa, which contains natural buffers to help with his stomach acidity. It is also important to minimize any changes in routine, and to treat him with medications (specifically,UlcerGard) beginning 3-5 days prior to any trailer rides or stressful events.

Besides management, it is also ideal to keep your horse on some form of medication or supplement preventative. While it is true that the brand name omeprazole pastes GastroGard and UlcerGard are the only FDA-approved and scientifically proven treatment and preventative, respectively, for Equine Gastric Ulcer Syndrome (EGUS), I understand that keeping him on UlcerGard indefinitely can be cost-prohibitive. You are correct that many other formulations of omeprazole have been tested for efficacy for treatment of EGUS and have shown a lack of significant effect. Therefore, for treatment of ulcers, the omeprazole powder is not likely to be helpful to your horse.

That said, scientific studies have not focused on testing medications in terms of their effectiveness as prevention for gastric ulcers. Therefore, veterinary practitioners resort to a variety of medications which are believed to have some positive effect on gastric ulcers, such as ranitidine and compounded omeprazole, for prevention. There are also feed additives and nutraceuticals such as aloe vera juice, buffering supplements, and prebiotic/psyllium products. Due to the small number of published research trials on preventing ulcers, there is no true right or wrong answer in terms of which medication or supplement you use. Most recently, a Norwegian feed additive called ImproWin, which is a combination of B vitamins and salts of organic acids, has been shown in a research trial to assist in equine ulcer healing. I hope you can use this information to formulate a strategy that best works for you and your horse.