Stomach Ulcers in Dogs: Causes, Signs & Treatment

Quick Answer
  • Stomach ulcers in dogs are sores in the stomach lining that usually happen because of another problem, especially NSAID use, liver disease, kidney disease, severe illness, or certain tumors.
  • Common warning signs include vomiting, vomiting blood, black tarry stool, poor appetite, belly pain, weakness, and pale gums from blood loss.
  • Proton pump inhibitors such as omeprazole are commonly used because they reduce stomach acid more effectively than H2 blockers, and many uncomplicated ulcers heal over about 4 to 6 weeks when the cause is addressed.
  • See your vet immediately if your dog vomits blood, passes black stool, seems weak or collapsed, has a painful swollen abdomen, or may have gotten into ibuprofen, naproxen, or aspirin.
Estimated cost: $250–$10,000

What Are Stomach Ulcers in Dogs?

Stomach ulcers, also called gastric ulcers, are open sores that form when the stomach's protective lining breaks down. Once that barrier is damaged, stomach acid and digestive enzymes can injure deeper tissue. Some ulcers stay shallow, while others extend deeper into the stomach wall and bleed.

Dogs with ulcers may have mild signs at first, like nausea, lip licking, or eating less. Others become sick quickly, especially if the ulcer is bleeding. Blood loss can lead to anemia, weakness, and pale gums. In severe cases, an ulcer can perforate, meaning it creates a hole through the stomach wall and leaks stomach contents into the abdomen. That is a life-threatening emergency.

Most ulcers are not a stand-alone disease. They are usually a consequence of something else, such as medication side effects, toxin exposure, major illness, organ disease, or cancer. That is why treatment often involves both protecting the stomach and figuring out what caused the ulcer in the first place.

Signs Your Dog May Have a Stomach Ulcer

  • Vomiting, especially repeated vomiting or vomiting on an empty stomach
  • Vomiting blood that looks bright red or dark like coffee grounds
  • Black, tarry stool (melena), which suggests digested blood
  • Poor appetite, nausea, lip licking, or drooling
  • Weight loss over days to weeks
  • Abdominal pain, hunched posture, restlessness, or reluctance to be touched around the belly
  • Lethargy, weakness, or exercise intolerance
  • Pale gums, which can happen with blood loss anemia
  • Sudden collapse, severe weakness, or a tense painful abdomen in emergency cases

Some dogs with ulcers show vague stomach upset at first, while others have obvious bleeding. Vomiting blood or passing black stool should be treated as urgent. Pale gums, collapse, a distended painful abdomen, or rapid worsening can point to major blood loss or perforation. See your vet immediately if any of those signs are present.

What Causes Stomach Ulcers?

Stomach ulcers in dogs usually develop when the stomach lining is injured or when acid overwhelms the stomach's normal defenses. According to veterinary references, the most commonly reported causes in dogs are NSAID use, neoplasia, and liver disease. NSAIDs can damage the stomach directly and also reduce protective prostaglandins that help maintain blood flow and mucus production in the stomach lining.

Medication-related causes include veterinary NSAIDs such as carprofen, meloxicam, deracoxib, and others, plus accidental exposure to human pain relievers like ibuprofen, naproxen, or aspirin. The risk rises when NSAIDs are overdosed, combined with corticosteroids, or used in dogs who are already dehydrated or medically fragile.

Disease-related causes include liver disease, kidney disease, severe systemic illness, shock, sepsis, heatstroke, mast cell tumors, gastrin-secreting tumors, and some primary stomach or intestinal cancers. Foreign bodies, caustic substances, and major physiologic stress can also contribute. Helicobacter organisms can be found in some dogs, but their exact role in causing ulcers is less clear than it is in people.

Because ulcers are often secondary, your vet may recommend looking beyond the stomach itself. Finding the underlying trigger can make the difference between short-term improvement and repeated flare-ups.

How Are Stomach Ulcers Diagnosed?

Diagnosis starts with history and physical exam. Your vet will want to know about recent NSAID use, steroid use, access to human medications, vomiting, stool color, appetite changes, and any history of liver disease, kidney disease, cancer, or toxin exposure. A complete blood count and chemistry panel are often the first step because they can show anemia, dehydration, kidney or liver changes, and electrolyte problems.

Imaging may help, especially if your dog is painful, vomiting repeatedly, or there is concern for a mass, foreign body, or perforation. Abdominal ultrasound can sometimes show thickened stomach tissue, free abdominal fluid, or other abnormalities. X-rays may help identify free abdominal gas if perforation is suspected, though they do not confirm every ulcer.

Endoscopy is the most definitive test for many dogs. It allows your vet to directly visualize the stomach lining and collect biopsies if needed. That can help confirm ulceration and rule out cancer or other diseases that can mimic a simple ulcer. In some straightforward cases, especially when there is a strong history of NSAID exposure and no signs of perforation, your vet may begin treatment before pursuing endoscopy.

Additional testing may include clotting tests, fecal testing, blood pressure assessment, ACTH stimulation testing if Addison's disease is a concern, or tumor staging if a mast cell tumor or other cancer is suspected.

Treatment Options for Stomach Ulcers

Spectrum of Care means you have options. Here are treatment tiers at different price points.

Conservative: Focused Medical Care

$250–$900
Best for: Dogs with mild to moderate suspected ulcers who are stable, still hydrated, and do not have signs of severe bleeding, perforation, or a suspected abdominal mass
  • Office exam and medication review
  • Basic bloodwork, often a CBC with or without chemistry panel
  • Stopping the suspected ulcer-triggering medication under veterinary guidance
  • Proton pump inhibitor such as omeprazole
  • Sucralfate to coat irritated tissue
  • Anti-nausea medication if needed
  • Short-term bland or easily digestible diet plan
  • Recheck visit in 1 to 2 weeks
Expected outcome: Often good when the trigger is identified early and removed. Many uncomplicated ulcers improve within several days and are treated for about 4 to 6 weeks.
Consider: Lower upfront cost and less invasive, but it may not identify deeper causes such as cancer, severe organ disease, or a hidden foreign body.
Most Common

Standard: Diagnostic Workup Plus Medical Treatment

$1,200–$3,800
Best for: Dogs with vomiting blood, black stool, anemia, ongoing pain, repeated vomiting, unclear cause, or concern for a mass, organ disease, or recurrent ulceration
  • Comprehensive exam and full bloodwork
  • Urinalysis and clotting tests when indicated
  • Abdominal ultrasound and/or radiographs
  • Hospitalization for IV fluids if dehydrated or actively vomiting
  • Proton pump inhibitor therapy, often omeprazole or pantoprazole
  • Sucralfate and other gastroprotective support when appropriate
  • Endoscopy with biopsy in selected cases
  • Treatment plan for the underlying disease, such as liver support, kidney care, or tumor workup
Expected outcome: Good to fair in many cases, depending on the underlying cause. Outcomes are strongest when both the ulcer and the reason it formed are addressed.
Consider: More complete information and a more tailored plan, but higher cost range and possible anesthesia for endoscopy.

Advanced: Emergency Stabilization and Surgery

$4,500–$10,000
Best for: Dogs with perforation, shock, severe GI bleeding, collapse, septic abdomen, or ulcers linked to tumors or other surgical disease
  • Emergency exam and stabilization
  • IV fluids, pain control, and intensive monitoring
  • Blood typing and transfusion if severe blood loss anemia is present
  • Injectable acid suppression such as pantoprazole in hospital
  • Emergency imaging and abdominal fluid assessment
  • Surgery for perforated ulcer, uncontrolled bleeding, foreign body, or tumor-related ulceration
  • ICU-level hospitalization and postoperative care
  • Biopsy or tumor removal when appropriate
Expected outcome: Guarded to fair for perforated ulcers and severe hemorrhage. Prognosis depends on how quickly treatment starts, whether contamination of the abdomen has occurred, and what underlying disease is found.
Consider: Highest cost range and most intensive care. It can be lifesaving, but recovery may be prolonged and the long-term outlook may still depend on cancer or organ disease.

Cost estimates as of 2026-03. Actual costs vary by location, clinic, and individual case.

Questions to Ask Your Vet About Stomach Ulcers

Bring these questions to your vet appointment to get the most out of your visit.

  1. You can ask your vet whether any current medications, including pain relievers or steroids, could be contributing to the ulcer.
  2. You can ask your vet which warning signs mean same-day recheck versus emergency care, especially if you see black stool or blood in vomit.
  3. You can ask your vet whether bloodwork alone is enough to start, or whether ultrasound, X-rays, or endoscopy would change the plan.
  4. You can ask your vet how long acid-reducing medication is usually needed and how to give it for the best effect.
  5. You can ask your vet whether sucralfate, misoprostol, or anti-nausea medication makes sense for your dog's specific situation.
  6. You can ask your vet what underlying diseases should be ruled out, such as liver disease, kidney disease, Addison's disease, mast cell tumor, or a foreign body.
  7. You can ask your vet what diet is appropriate during recovery and when your dog can return to normal food.
  8. You can ask your vet what monitoring is needed after treatment, including repeat bloodwork, stool checks, or follow-up imaging.

How to Prevent Stomach Ulcers

Prevention starts with medication safety. Never give human pain relievers like ibuprofen or naproxen unless your vet specifically instructs you to do so. These drugs can cause stomach ulcers and kidney injury in dogs, sometimes after a small exposure. If your dog is prescribed a veterinary NSAID, give it exactly as directed and let your vet know right away if you notice vomiting, poor appetite, black stool, or lethargy.

It also helps to avoid risky drug combinations. NSAIDs and corticosteroids together can sharply increase ulcer risk, so your vet will usually avoid overlapping them unless there is a very specific reason. Dogs on long-term pain control or dogs with liver disease, kidney disease, or cancer may need closer monitoring and periodic lab work.

If your dog has a history of ulcers, ask your vet before starting any new medication or supplement. Keep all human medications secured, follow recheck recommendations, and do not assume mild stomach upset is harmless in a dog taking NSAIDs. Early action can prevent a manageable ulcer from becoming an emergency.

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