Ulcer Treatment for Horses: Why and what to do?

It's not uncommon for a horse owner to face a situation where they feel their horse is not performing, not eating well, or just doesn't look right. The problem, pure and simple, could be gastric ulcers, where the horse suffers from equine gastric ulcer syndrome (EGUS) -an ulceration of the oesophageal, gastric or duodenal mucosa.

Understanding horse ulcer treatment is essential for every owner. Did you know that endoscopic procedure has revealed that nearly 90 per cent of examined racehorses and up to 60 per cent of performance horses have gastric ulcers? Even more importantly, this syndrome doesn't affect only the equine athlete. Studies have shown that all horses are at risk (Even newborns and yearlings!) with occurrence rates of up to 50 percent.

How do gastric ulcers develop

Horses differ from humans because they secrete stomach acid continuously, even when not eating. Adult horses secrete 30 litres of gastric acid daily. When horses are unable to access food on a continual basis, such as when grazing, the pH balance of the stomach changes drastically and gastric juices begin to attack the stomach mucosa. Acid produced in the stomach is generally buffered by saliva which contains a high concentration of bicarbonate and mucus.

If access to feed is limited, then consequently the horses' saliva production is reduced. As a result the squamous portion of the horse's stomach, the most common part to be affected, lacks the buffer bicarbonate and protective mucous coating to protect the stomach lining from acid.

Various feed stuffs produce different amounts of saliva. For example, 1kg of hay takes 3000 chewing movements and produces 4 litres of saliva, versus 1kg of grain, which takes only 1000 chewing movements and produces 2 litres of saliva.

Stressful environments, travelling and restricted diets can contribute to ulcers developing

(Photo above: Stressful environments, travelling and restricted diets can contribute to ulcers developing)

What causes ulcers in horses?

The biggest cause of ulcers in horses are diet and feeding behaviour. Horses on pasture have the lowest incidence of ulcers compared to those athletes that need "high-energy" concentrates (a smaller portion of their diet is hay). Thus, it is believed the increased rate of ulcers in horses is due to a combination of factors including:

  • A high-concentrate diet with low-roughage intake (especially when only fed once or twice a day).
  • Withholding feed during competitions.
  • Intensive exercise on an empty stomach. This can cause splashing of acid onto vulnerable parts of the stomach.
  • Stressful environments, including physical stress such as illness and behavioural stress such as stall confinement, long-distance transportation or unfamiliar environments.
  • Use of Non-Steroidal Anti-Inflammatory Drugs (e.g. Phenylbutazone or Flunixin meglumine)

Clinical signs your horse may have ulcers

Clinical signs can be non-specific and are not unique to gastric ulcers. The signs of ulcers often match a range of common complaints experienced by horses. This highlights the need for proper diagnosis by a veterinarian to determine exactly what you are dealing with.

In adult horses these include:

Poor appetite, colic, decreased performance, attitude change, poor body condition and weight loss

In foals (or young horses) these include:

Intermittent nursing, poor appetite, intermittent colic, poor body condition, diarrhoea, teeth grinding, salivation, pot belly and rough hair/coat.

However, owners and trainers should inquire about ulcer treatment for horses if any or all of the signs are observed or reported in the horse.

Girthy horse? It could be ulcers

(Photo above: Is your horse unhappy when the girth is tightened? It could be a pain response caused by ulcers)

Diagnosing Ulcers in Horses

There is only one sure way to confirm ulcers, Esophagogastroscopy, or simply "stomach scoping." No food is to be fed six to eight hours before scoping. A light sedative is given five minutes before the passing of the three-meter scope, similar to passing a stomach tube, down the horse's oesophagus.

The severity of stomach ulcers is rated in grades from an inflamed but intact epithelium (Grade 0 ulcer), superficial erosions of the mucosal surface (Grade 1 ulcer) to single superficial erosions of the mucosal surface (Grade 2 ulcer) to multiple actively haemorrhaging hyperaemic (Grade 3 ulcer).

Depending on the grade, ulcer treatment may be required for your horse.

Ulcer Treatment for Horses

Veterinary treatment

Once the ulcer condition is known, what does ulcer treatment for horses look like? The acid pump in the horse's stomach producing gastric juices needs to be suppressed.

Pasture and free access to hay is the most natural and least ulcerogenic environment. Forage consumption not only slows speed of feeding, but also stimulates saliva that acts as a protective buffering agent. This dietary ulcer treatment can be great for your horse.

Racehorses and performance horses generally heal faster if removed from training and competition.

Horses with documented gastric ulcers have responded to histamine H2-receptor antagonists, such as cimetidine and ranitidine, commonly known as H2 blockers. Although H2 blockers may provide limited, symptomatic relief, they block only one of several sites that stimulate acid production and may not heal the underlying gastric lesion.

A newer approach to the treatment of gastric ulcers is the introduction of the proton-pump inhibitors, also referred to as the acid-pump inhibitors. This is the "gold standard" for ulcer treatment in humans and promises to be a cure for ulcers in horses. The major advantage is this treatment has the same active ingredient, omeprazole, as in human ulcer medication.
Administered daily, the acid-pump will effectively block the production of gastric acid throughout the 24 hours after administration - making it an extremely effective ulcer treatment for horses.

The only problem that arises with the use of these products is that they have to be taken off these medications prior to competition. This increases the risk of the ulcers reoccurring or not healing properly and thus will affect performance.

Nutritional options for prevention

First and foremost, it's essential to have the correct foundation for your horse's diet. Every diet needs adequate roughage to ensure that the horse is chewing and digesting all day long. Avoid long periods without food and feed frequent small meals. Ad lib hay/pasture is ideal. If feed is withheld, the pH in the stomach drops rapidly.

To further protect your horse's stomach you can feed a small amount of lucerne chaff or hay prior to work. Lucerne helps in two ways: by acting as a physical barrier, and secondly, the calcium in the lucerne buffers the acid. 

Many nutritional supplements are available that aim to support the horse's digestive health and prevent ulcers from occurring. These products may also assist the recovery and prevent reoccurrence after an ulcer episode.

Several herbs have been used to aid in the treatment of symptoms of ulcers in horses. Comfrey leaf, Marshmallow Root, Liquorice, Meadowsweet and Slippery Elm have all show signs of mucilaginous properties, which aid in providing a mucous layer over the stomach lining. 

Naturally derived Antacids, such as Red Seaweed, can be effective at increasing the pH of the stomach, thereby decreasing the risk of ulcer formation.

Some products may not work as quickly as prescription drugs, so allow the product enough time to take affect, as recommended by the manufacturer.  

 Digestive support for horses

HYGAIN® DIGEST & PROTECT® provides complete digestive support in a palatable blend, formulated to stimulate digestion and promote the health of the digestive tract.

The formulation of DIGEST & PROTECT contains:

RED SEAWEED EXTRACT (Lithothamnion calcareum), is rich in a specific, highly effective source of calcium, known for its superior acid buffering properties.

DIGESTIVE ENZYMES support the breakdown of feed which improves digestion and the absorption of nutrients.

GLUTAMINE & THREONINE, amino acids assist with digestive health. Included to ensure adequate supply to support mucin synthesis and cell regeneration.

CONCENTRATED SLIPPERY ELM traditionally used for gastric challenges. Slippery Elm contains mucilage factors which act as a coating agent.

CURCUMIN, is the active compound in Turmeric known for its powerful antioxidant action.

PREBIOTICS have a defined mode of action, promoting a healthy gut and supporting natural defences essential for optimum health and performance.

PROBIOTICS enhance fibre fermentation and stablilise the microbiome, stimulating activity of beneficial bacteria in the digestive tract.

MYCOTOXIN BINDER traps and expels mycotoxins to protect and support healthy gut function.

ANISEED flavour is highly palatable for horses.

Equine digestive supplement


A recap of ulcer prevention in horses

  • Avoid long periods without food. Feed frequent small meals.
  • Feed ad lib hay - If feed is withheld, the pH in the stomach drops to 2 in 21 hrs.
  • Place feed bins on the ground to simulate the horse’s normal grazing position as it helps his chewing action, stimulating the production of more saliva which in turn helps the passage of food to the stomach.
  • Do not exercise on an empty stomach as this allows acid to attack the stomach wall when it is empty. 
  • Feed a small amount of lucerne chaff or hay prior to work. Lucerne helps in two ways by acting as a physical barrier and secondly the calcium in the lucerne buffers the acid.
  • Avoid physical and behavioural stress.
  • Avoid long treatments with non-steroidal anti-inflammatory drugs such as Phenylbutazone.


Just as diet and feeding habits can be the solution, they are also instrumental to preventing ulcers in the first place.

Equine Gastric Ulcer Syndrome is a major cause of underlying illness in performance horses and therefore impacts the health and performance of the horse. Make sure the horse’s diet includes access to pasture, adlib hay and highly soluble fibre sources, especially if they are stabled. This assists them in producing saliva, which in turn helps to buffer stomach acid.

Reduce or remove stress factors affecting the horse and seek treatment from your veterinarian. Remember effective treatment entails environmental, behavioural and dietary management as well as medical intervention.

Want to talk further about your horse's specific needs?

Our nutrition advisors at Nutrikey offer a free diet analysis that is simple, fast, and accessible to all levels and disciplines of horse owners. The team will review your horse's current diet, considering all of their lifestyle factors to provide a diet plan that will help them look and feel their best. Visit nutrikey.com.au or reach out to nutrition@hygain.com.au

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