Does Your Dog Have Stomatitis?
Stomatitis goes well beyond ordinary gum disease. Here's what's causing it and what treatment actually looks like.
If your dog has bright red, raw-looking gums, breath that clears a room, and has started dropping food or refusing to eat, this is more than ordinary gum disease. What you’re likely seeing is stomatitis, a condition where the mouth’s soft tissues become severely inflamed, often to the point of open sores. It’s painful, it’s progressive, and it needs attention. Here’s what’s happening and what you can do about it.
TL;DR
- Stomatitis in dogs is severe, painful mouth inflammation that goes well beyond gingivitis. It’s often an immune overreaction to plaque (called CCUS or CUPS).
- Signs include raw or ulcerated gums, “kissing ulcers,” extreme bad breath, drooling, dropping food, pawing at the mouth, and weight loss.
- Diagnosis usually involves an oral exam under anesthesia, dental X-rays, and a biopsy to rule out other causes.
- Treatment ranges from strict plaque control and medication to full-mouth extraction, which can actually resolve the condition when plaque control alone isn’t enough.
What is stomatitis in dogs?
Stomatitis means inflammation of the soft tissues inside the mouth, including the gums, tongue, cheeks, and throat. In dogs, the most common form is canine chronic ulcerative stomatitis (CCUS), also called canine ulcerative paradental stomatitis (CUPS). The key word there is “ulcerative”: it doesn’t just mean red or irritated. It means open, painful sores.
What makes this condition different from regular gum disease (gingivitis) is the immune system’s role. In dogs with CCUS, the immune system essentially overreacts to the bacteria in dental plaque. Even a small amount of plaque triggers an intense inflammatory response that breaks down the tissue. The result is raw, ulcerated gums that can bleed, and in some cases, lesions that develop where the inner lip or cheek presses against the teeth. Vets call these “kissing ulcers” because they form at the contact point.
What are the signs of stomatitis in dogs?
Because this condition is so painful, many of the signs show up in how your dog eats and behaves, not just in how their mouth looks. Watch for:
- Bright red, raw, or ulcerated gums (the tissue may look like it’s wearing away)
- Kissing ulcers on the inner lips or cheeks where they touch the teeth
- Severe bad breath, much worse than typical “dog breath”
- Heavy drooling, sometimes with blood-tinged saliva
- Dropping food or chewing only on one side of the mouth
- Pawing at the mouth or face
- Reluctance to let anyone near the mouth
- Weight loss from avoiding eating altogether
If your dog is losing weight because eating hurts too much, that’s a signal to get to a vet promptly. Oral pain at this level is not something to wait out.
What causes canine stomatitis?
In most cases, the root trigger is plaque. Dogs with CCUS or CUPS have an immune system that treats ordinary plaque bacteria like a serious threat, launching an inflammatory response that damages the tissue instead of protecting it. It’s plaque-reactive and immune-mediated, meaning the immune system is driving the damage.
That said, a few other factors can contribute or make things worse:
- Underlying dental disease or tooth root infections
- Systemic illness (kidney disease, for example, can worsen mouth inflammation)
- Viral infections in some cases
- Genetic predisposition in certain breeds, though any dog can develop it
How do vets diagnose dog stomatitis?
Because the mouth is painful, a proper exam almost always requires general anesthesia. Your dog needs to be comfortable and still for the vet to see the full picture safely.
A full diagnosis typically involves:
- Oral exam under anesthesia: The vet gets a complete look at every surface in the mouth, including under the tongue and behind the back teeth.
- Dental X-rays: These show what’s happening below the gum line, including tooth root infections or bone loss that aren’t visible from the surface.
- Biopsy: The vet takes a small tissue sample from an affected area and sends it to a lab. This confirms the diagnosis and, crucially, rules out other causes of mouth sores, like oral tumors.
What are the treatment options for stomatitis in dogs?
There’s no one-size-fits-all protocol here. Your vet will build a plan based on how severe the inflammation is and how your dog’s mouth responds. Most approaches involve a combination of the following.
Rigorous plaque control
Since plaque is the trigger, eliminating it is the first goal. Your vet may recommend professional cleanings under anesthesia every few months, antimicrobial rinses, and, if tolerated, daily brushing with a dog-safe toothpaste.
Medication
Anti-inflammatory drugs, immunosuppressants (medications that dial down the immune response), and antibiotics may all be part of the picture. These can help manage flare-ups but often need to continue long term.
Extractions, including full-mouth extraction
This is the part that surprises most owners: removing teeth, sometimes all of them, can actually resolve canine stomatitis. Here’s the logic. If the immune system is reacting to plaque on the teeth, removing the teeth eliminates the surface plaque clings to. No teeth, no plaque, no trigger. Many dogs go into complete remission after full-mouth extraction and do extremely well without their teeth. They can still eat soft food comfortably, often with far less pain than before the procedure.
Strategic extraction (removing only the most affected teeth) may be tried first, especially in milder cases, but full-mouth extraction is often the most effective long-term solution when other approaches haven’t worked.
Does pet insurance cover stomatitis in dogs?
Coverage for stomatitis depends on what’s causing it. If it’s immune-mediated, it may be covered under Lemonade Pet’s base accident and illness policy. If it’s driven by periodontal disease, you’ll need one of Lemonade Pet’s dental add-ons. Either way, the condition needs to develop after your policy starts and waiting period passes to be eligible.
Stomatitis treatment isn’t cheap. Anesthetized dental procedures, X-rays, biopsies, extractions, and long-term medication add up quickly. Getting the right coverage in place before symptoms appear is what makes it actually useful when you need it.
Before we go
Stomatitis is painful and persistent, but it’s also treatable. Many dogs see dramatic improvement after the right intervention, whether that’s rigorous plaque control, medication, or full-mouth extraction. Stay consistent with at-home care, keep up with your vet’s recommended cleaning schedule, and don’t put off treatment if your dog is clearly in pain. The sooner it’s addressed, the better the outcome.
Frequently Asked Questions
Is stomatitis the same as gingivitis in dogs?
No. Gingivitis is inflammation of the gums, usually from plaque buildup, and is common and treatable. Stomatitis is more severe, involving the broader soft tissues of the mouth and often open ulcers. It’s driven by an immune overreaction and requires a more intensive treatment plan.
What are kissing ulcers in dogs?
Kissing ulcers are sores that form on the inner surface of the lips or cheeks where they make contact with the teeth. They’re a hallmark sign of canine ulcerative paradental stomatitis (CUPS) and are a sign that the inflammation is severe.
Can I manage my dog’s stomatitis at home?
Home care, like soft food feeding and gentle antimicrobial rinses, can help keep your dog comfortable and reduce bacterial load between vet visits. But stomatitis requires professional diagnosis and treatment. Home care alone won’t resolve the underlying condition.
Will my dog be okay after full-mouth extraction?
Most dogs do very well. They adapt quickly to eating soft food and are often dramatically more comfortable after the procedure than they were with a painful, inflamed mouth full of teeth. Many owners report their dog seems like a different, happier animal after recovery.
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