HORSES · OWNER EDUCATION
Equine Gastric Ulcer Syndrome
Stomach ulcer disease can contribute to poor appetite, behavior change and reduced performance, but these signs are not specific.
THE SHORT VERSION
What matters for your animal?
Start with the warning signs and when-to-contact sections if your animal is unwell. The same outward change can have several causes, so this guide helps you prepare questions rather than identify a diagnosis on your own.
What is this condition?
Stomach ulcer disease can contribute to poor appetite, behavior change and reduced performance, but these signs are not specific. Similar signs can have very different causes, so the animal's species, husbandry, examination findings and diagnostic results all matter.
Gastric ulcers can occur in different regions of the stomach, and vague changes in appetite or performance do not identify them reliably. Investigation helps distinguish ulcer disease from other causes of discomfort. Feeding and management may influence the plan, but treatment is selected for the diagnosed problem. Ask how response will be assessed rather than assuming that a trial of medication proves the original cause.
Digestive signs describe what the animal is doing, rather than a single disease. The problem may be in the digestive tract itself or may reflect pain, metabolic illness, toxins, or another body-wide condition. Fluid loss and reduced food intake can become important complications even before the exact cause is confirmed. The investigation considers the timeline, diet, access to foreign material, stool output, and other signs. This helps distinguish a problem that may respond to medical support from one that needs urgent intervention.
Which species does this guide cover?
The species listed above are the focus of this guide, rather than a complete list of every animal that can develop this condition. Causes, testing and treatment may differ between species and individual patients.
Why can it happen?
- Acid exposure, feeding pattern, intense exercise, transport and stress.
- Different stomach regions have different risk factors and treatment needs.
Inflammation is the body's response to irritation or injury. It can produce swelling, discomfort, and changes in how an organ works, but the word does not identify the cause. Infection, immune activity, trauma, and other processes can all cause inflammation. This distinction matters because an antibiotic treats susceptible bacteria, while inflammation caused by a different process needs a different plan. A temporary improvement in redness or discomfort does not, by itself, establish which cause was present.
What might an owner notice?
- Reduced appetite, girth sensitivity, behavior change or poor performance.
- Weight loss, recurrent mild colic or poor body condition.
How is the problem investigated?
History and examination with gastroscopy for a reliable diagnosis. Assessment for other causes of pain, weight loss or poor performance.
Explore the diagnostic testing library →What might treatment involve?
Veterinarian-directed acid suppression or other medication based on ulcer location. Forage access, feeding and training changes tailored to the horse.
This is an overview, not a prescription or a recommendation for a specific individual animal.
What can owners do at home?
Record appetite, water intake, waste output, activity, breathing and body weight when it is safe to do so. Photograph the enclosure, food labels or flock environment and bring a concise timeline to the veterinary visit. Follow the veterinarian's exact instructions for medication, feeding, isolation, rechecks and environmental correction.
Comfort is assessed through behavior and function as well as obvious crying or vocalization. Changes in posture, movement, grooming, sleep, social interaction, or willingness to be handled can be useful clues. Compare the animal with its own normal behavior rather than with another animal. Keep a short record of what it can do comfortably and share changes with the care team. If pain control appears inadequate, contact the veterinarian; increasing a dose or combining medicines without advice can introduce serious risks.
A feeding plan should account for the actual food eaten, not just the amount offered. Selective eating, dropped food, hidden leftovers, and competition can make intake difficult to judge. Record the food type, measured portion, treats, and any supplements so the team can assess the complete diet. A disease-specific diet or assisted feeding may be recommended in some cases, but force-feeding is not a safe default for an animal that cannot swallow normally or may have an obstruction.
Avoid actions that could make care less safe.
- Do not give human medication, leftover antibiotics, livestock medication or another animal's treatment without veterinary direction.
- Do not force-feed an animal that is struggling to breathe, cannot swallow, is severely weak or may have an obstruction.
- Do not delay care when appetite, breathing, urination, movement or responsiveness changes rapidly.
What can the longer-term outlook involve?
The outlook varies with the cause, severity, how quickly care begins and whether the animal's environment or nutrition can be corrected.
A recheck is not simply a repeat of the first appointment. It assesses whether the original problem is improving, whether complications are appearing, and whether the treatment remains appropriate. The useful measures may include comfort, function, intake, body weight, examination findings, or selected tests. Ask which changes are expected before the visit and which should trigger an earlier call. Improvement in one sign does not always mean that every part of the disease has resolved.
Can risk be reduced?
Provide species-appropriate nutrition, housing, sanitation and preventive veterinary care. Learn the individual's normal appetite, behavior, body condition and waste pattern so change is recognized early.
When should you arrange care?
- Contact a veterinarian promptly for reduced appetite, girth sensitivity, behavior change or poor performance. or weight loss, recurrent mild colic or poor body condition..
- Arrange reassessment if signs recur, treatment is not working or another animal becomes affected.
Seek urgent veterinary advice if you notice:
DO NOT DELAY URGENT CARE- Severe colic, collapse, repeated rolling or black tarry manure.
What information helps the care team?
Record which animals are affected, feeding or housing changes, recent arrivals, treatments and any losses. For a flock or herd problem, the number affected and the pattern over time may be as important as one animal's examination.
How should you understand the tests?
Ask what each proposed test is intended to answer. Some tests identify a cause; others assess severity, organ function or treatment safety. Results are interpreted with the examination and history. A normal result does not exclude every problem, and an abnormal result does not always explain every sign.
Questions to ask before leaving
- What is confirmed, and which other explanations are still being considered?
- What changes should we expect with the proposed plan, and when should we reassess if they do not occur?
- Which observations should I record, and which changes mean I should call sooner?
- What medicine or home-care problems should I report, and what are the instructions for a missed dose or suspected side effect?
- When is the recheck, what will it assess, and whom should I contact after hours?
A care plan may be adjusted as results or the response become clearer. Keep the written instructions and tell the team if cost, handling or administration difficulty makes the plan hard to follow.
Sources behind this guide
VeterinaryPartner — client education from the Veterinary Information NetworkVeterinary, university or animal-health guidance ↗American Association of Equine Practitioners: horse-owner resourcesVeterinary, university or animal-health guidance ↗Content last reviewed: September 17, 2026. Review status: veterinary-informed; independent veterinarian review not yet completed.