Gastric ulcers are far more common than most people realise – and the good news is, with the right care, they’re usually very manageable.
I see ulcer-related issues regularly, across performance horses, pleasure horses, and even those in light work. This guide is designed to help you understand when horses are most at risk of gastric ulcers and how to reduce the risk of them coming back, because long-term gut health is about more than just medication.
How Do Gastric Ulcers Develop?
Horses are incredible animals – giant herbivores designed to eat little and often, almost constantly. Their stomachs produce acid 24 hours a day, continuously, regardless of whether there’s food present.
When a horse grazes or eats hay…
- They chew side-to-side
- Saliva is produced, which contains bicarbonate (a natural buffering agent)
- Food mixes with saliva before being swallowed
This natural process is essential for gastric health. It helps break down food and protects the stomach lining by buffering acid.
Now let’s change that natural setup…
- Remove forage
- Put your horse on a float or truck for a few hours
- Stand them around at a show
- Then ask them to perform
This creates the perfect storm.
We now have…
- An empty stomach
- Ongoing acid production
- Very little buffering saliva
- Exercise causes acid to splash upwards inside the stomach
Repeat this scenario often enough, and the acid begins to damage the stomach lining, particularly in the more vulnerable areas. That’s how gastric ulcers develop.
I’m not saying we shouldn’t travel or compete with our horses, not at all. We just need to be mindful of when, how, and what we feed, so we can support them properly.
Squamous vs Glandular Ulcers: What’s the Difference?
Affect the upper, non-glandular portion of the stomach. This area has no natural acid protection.
Squamous Ulcers (ESGD)
Commonly associated with…
- Intermittent feeding or fasting
- Exercise on an empty stomach
- Transport
- High-grain, low-forage diets
- Stress
These are the most common ulcers seen in performance horses and are closely linked to management practices.
Glandular Ulcers (EGGD)
Affect the lower, glandular portion of the stomach. This area normally produces mucus and bicarbonate
Often associated with…
- Stress
- Pain or chronic inflammation
- NSAID use
- Hormonal influences
Glandular ulcers may heal more slowly and may require longer-term management.
How Common Are Gastric Ulcers?
Updated large-scale scoping studies and laboratory-aligned data show…
- 60–90% of performance horses have gastric ulcers
- Over 50% of pleasure horses may be affected
Ulcers are commonly found in…
- Racehorses
- Jumpers
- Dressage horses
- Pony club mounts
- Broodmares and young stock
If you’re wondering whether ulcers could be contributing to changes in your horse, it’s a very real possibility.
Signs Your Horse May Have Gastric Ulcers
Ulcer signs are often subtle and non-specific, and some horses are incredibly stoic.
Common signs include…
- Changes in temperament (grumpy, reactive, girthy)
- Picky eating or reduced appetite
- Poor performance or fatigue
- Sensitivity when brushed, especially around the girth
- Loose manure or intermittent diarrhoea
- Dull coat or weight loss
- Just seeming a bit “off”
There’s been growing interest in diagnosing ulcers using acupuncture points or behavioural patterns. These can be helpful screening tools, but they are not definitive.
Medical Treatment & Medications
Drug therapy is still the mainstay treatment of ulcers; however, diet and nutritional management provide long-term solutions to reduce the risk of recurrence and complications.
Without addressing the stress factors that caused the ulcers in the first place, the ulcers will quickly return, especially if your horse is kept in training.
Common medication options include…
The Gastropell Daily and Cale Gastro are both over-the-counter products that you can purchase without a vet prescription. Some gastric ulcer products are available without a prescription, but veterinary advice is still recommended, especially for severe, recurring, or non-responsive cases.
| Product | Dosage &Administration | Price / Daily Dose |
| Gastropell® Daily Oral Paste | Adult Horses: Treatment Dose – 10 mL/500 kg BW (1.0 mg/kg BW) once daily for 2 to 4 weeks, followed by daily maintenance dosing. Maintenance Dose: 5 mL/500 kg BW (0.5 mg/kg BW) once daily while horses remain in training, or as directed by a veterinarian. The maintenance dose may be insufficient to prevent recurrence of ulceration in horses subjected to increased stress, such as intense training, heavy competition schedules, or transport. Foals: 2 mL/100 kg BW (1.0 mg/kg BW) once daily or as directed by a veterinarian. | $176.56 per 5 x 30 mL and/or $1,485.00 per 50 x 30 mL |
| Gastropell® Forte Oral Paste | Adult Horses: Treatment Dose: 10 mL/500 kg BW (2.0 mg/kg BW) once daily for 2 to 4 weeks, followed by daily maintenance dosing. Prevention/Maintenance Dose: 5 mL/500 kg BW (1.0 mg/kg BW) once daily whilst the horse remains in training. | $337.84 11mg/ml 5 X 30 mL |
| Ulcershield® Oral Paste | Treatment Dose: 4 mg/kg. Adult horses (600 kg) give 6 mL (1 mL per 100 kg) daily for 28 days. Prevention/Maintenance Dose: 1 mg/kg. Adult horses (600 kg) give 1.5 mL (0.25 mL per 100 kg) daily for 28 days. | $401.70 per 6 x 33g sachets |
| CaleGastro | Administer orally at a dose rate of 5 ml/100 kg BW (1.5 mg/kg). Adult Horses (600 kg) administer 30 mL once daily, or as directed by a veterinarian. | $9.97 per 30 mL syringe |
| Equestra Equine Omeprazole | Give 1 2g sachet per 250kg body weight once daily for 4 weeks, then give 1 2g sachet per 500kg once daily for 4 weeks. One 2g sachet contains 500 mg Omeprazole. | $269.50 per 50 x 2g sachets |
Treatment is usually…
- Full dose for 28–30 days
- Followed by a gradual taper over 2–4 weeks
Some horses benefit from a preventative dose during periods of travel, competition, or increased workload.
These products are best given…
- On an empty stomach
- With no hard feed for 30 minutes afterwards
- Medication treats the ulcers, but management changes prevent their recurrence.
Key Points…
- Gastropell Daily and Cale Gastro are great for general treatment and maintenance in most horses.
- Gastropell Forte and Ulcershield are more concentrated and typically reserved for more severe or chronic cases
- Equestra sachets provide an alternative delivery form and higher bioavailability.
The Gold Standard for Diagnosis: Gastroscopy
The only way to accurately diagnose ulcers is via endoscopy (scoping).
This allows your vet to…
- Confirm whether ulcers are present
- Identify where they are (squamous vs glandular)
- Grade severity
- Tailor treatment
For first-time cases, some owners choose to trial treatment without scoping. If ulcers recur or don’t respond as expected, I strongly recommend scoping.
There are no reliable blood tests for ulcers, although chronic or severe cases may show secondary changes such as low protein or anaemia.
When Are Horses Most at Risk?
Ulcers usually develop due to a combination of factors, including:
- Exercise intensity
- Intermittent feeding or long fasting periods
- High-grain or high-starch diets
- Low forage intake
- Transport and competition
- Stress and anxiety
- Pain or chronic inflammation
- Regular NSAID use
Reducing Ulcer Risk & Preventing Recurrence
Long-term success relies on reducing the overall acid load and consistently supporting the gut.
Key strategies…
Ultimately, we need to reduce that acid load in the stomach. We need to ensure our horses are grazing or munching on hay as much as possible so they are constantly placing forage in their stomachs to buffer the acid.
- If you are travelling or heading to a competition, lucerne chaff and hay should be your best friend. The high calcium content of these products has been shown to be highly effective at reducing the acid load.
- Feeding a few handfuls of Lucerne chaff before riding provides a protective matting to help prevent acid splashback.
- If your horse gets a bit stressed in a stable or yard, they definitely need to be turned out to graze more often.
Just remember, the longer your horse doesn’t have food or a buffer in their stomach, the more acid is being produced that can cause harmful effects.
Can Supplements Help Support Gastric Health?
Supplements can support digestive health, particularly for horses in regular work, competition, or travel.
Some supplements commonly used to support gastric health include…
- Buffering products to help manage gastric acidity
- Digestive support formulas for sensitive horses
- Hindgut support supplements to promote overall gut balance
Just bear in mind that if you’re not addressing the root cause of the ulcers, they may not work; use them as part of your ongoing management plan. A great supplement we currently have is the KER Neigh-Lox.
Supplements work best as part of a broader management plan; they don’t replace good feeding practices, but they can help reduce the risk of recurrence when used appropriately.
Final Thoughts
Gastric ulcers are common, but they don’t have to be a constant issue.
With the right combination of…
- Veterinary treatment
- Smart feeding strategies
- Stress reduction
- Ongoing digestive support
Most horses can recover well and stay comfortable long-term.
If you have questions about ulcer management, feeding strategies, or choosing the right gastric ulcer support options, feel free to get in touch. I’m always happy to help.
