Black Gums and Stinky Breath. What’s Going on in Your Cat’s Mouth?


Cats with black gums and bad breath are exhibiting symptoms of dental disease, which is very common in cats. Studies show that between 50-90% of cats over 4 years old suffer from some form of dental disease ( The black coloration and foul odor are caused by plaque and tartar buildup on the teeth. If left untreated, this can lead to inflammation, tooth decay, and oral pain.

Dental disease progresses through various stages, from gingivitis (inflammation of the gums) to more severe periodontitis. Along the way, gum recession, tooth mobility, and eventual tooth loss can occur. The prevalence of dental issues highlights the importance of prevention and early treatment.


Some common causes of black gums and bad breath in cats include:

  • Periodontal disease: This is an infection in the tissues surrounding the teeth caused by plaque buildup. It can lead to gingivitis, receding gums, tooth loss, and bad breath (source).
  • Abscesses: Abscesses in the mouth often form at the root of a diseased tooth. The pus in the abscess can cause foul breath (source).
  • Oral tumors: Tumors in the mouth or on the gums can cause gum discoloration and bad breath. Oral tumors may be malignant or benign (source).
  • Ingested toxins: Exposure to toxins like heavy metals or poison can cause blackening of the gums and foul breath.


To determine the cause of bad breath and black gums in cats, veterinarians will perform a complete physical exam, focusing closely on the mouth, teeth and gums. They will look for signs of periodontal disease, oral tumors, and other abnormalities. Dental x-rays may be recommended to evaluate the health of the teeth below the gumline and look for tooth root infections. Biopsies can help rule out oral cancer or other diseases affecting the gums and oral cavity. Bloodwork and urinalysis may also be performed to check for issues like kidney disease that can lead to bad breath.

According to VCA Animal Hospitals, “The most common cause of halitosis in cats is periodontal disease caused from plaque and tartar build-up. Plaque-containing bacteria attaches over the freshly cleaned tooth surface within hours and begins to damage gums and teeth. Within days the bacteria are producing toxins which further inflame the gums.” Proper diagnosis is key to determining the underlying cause and appropriate treatment (


Treating black gums usually involves a professional dental cleaning by a veterinarian to remove plaque and tartar from the teeth and gums. According to the Cornell Feline Health Center, “To treat feline periodontitis, your veterinarian will recommend removing plaque and mineral buildup by scaling and polishing the teeth while trying to avoid trauma to the tooth enamel.”

In severe cases of gum disease, tooth extraction may be necessary if periodontal disease has damaged the tooth beyond repair. Extraction helps prevent further infection and pain. Antibiotics may also be prescribed to treat or prevent infections.

Pain medication, such as buprenorphine or meloxicam, can help relieve discomfort after dental procedures. It’s important to follow up regularly with the veterinarian after treatment to prevent recurrence of dental disease. With proper care, most cats recover well after professional dental cleanings and extractions.


Home Care

There are some steps cat owners can take at home to help care for their cat’s oral health and potentially improve black gums caused by plaque buildup or gingivitis:

Brushing teeth – Brushing your cat’s teeth regularly can remove plaque and tartar buildup. Use a soft bristled brush and cat-safe toothpaste. Introduce brushing slowly and make it a positive experience for your cat with treats and praise. Brushing just once or twice a week can make a difference.

Dental diets – Feeding your cat dental diet kibble or treats can help scrape away plaque and tartar. These foods are formulated to be crunchy and fibrous to naturally clean teeth as your cat chews. Consult with your vet on introducing a dental diet.

Oral rinses – Oral rinses like chlorhexidine can reduce bacteria when applied to your cat’s teeth and gums. Ask your vet if an oral rinse could help your cat in addition to brushing. Use caution when introducing to avoid swallowing and monitor for reactions. Apply the rinse by dipping a soft cloth or cotton swab and gently wiping on teeth and gums.

While home care can help mitigate existing plaque issues, regular dental cleanings by a vet are often needed to fully address the underlying problem. Be sure to follow up regularly with your vet even when providing home care.


The prognosis for a cat with black gums and bad breath depends on the underlying cause. However, with early diagnosis and proper treatment, the prognosis can be good. Some key points on prognosis include:

According to the Purina article (Stomatitis In Cats), if stomatitis is caught early, it can often be managed with professional dental cleanings and medications prescribed by a vet. However, if stomatitis progresses to a severe stage, it can be challenging to manage.

As explained in the CatBandit article (Why Do Cats’ Gums Turn Black?), periodontal disease is manageable when treated promptly before it advances to irreversible stages. With early intervention, the prognosis is good.

Treating the underlying condition, whether it is stomatitis, gingivitis, or another oral health issue, can help stop the progression of black gums and bad breath. Catching it early and following veterinary recommendations offer the best prognosis.


There are several ways to help prevent your cat from developing bad breath and black gums:

Regular dental cleanings by a veterinarian can remove built-up plaque and tartar before it leads to gingivitis and other dental disease. Veterinary dental cleanings are recommended at least annually for most cats.

Brushing your cat’s teeth daily using a soft bristled toothbrush and pet-safe toothpaste is the most effective way to remove plaque at home. This helps reduce tartar buildup and keep your cat’s mouth healthy.

Feeding dental diets designed to reduce plaque and tartar can also help prevent dental disease. These diets have larger, crunchier kibbles that scrape the teeth during chewing.

Oral rinses containing chlorhexidine or other anti-plaque ingredients can reduce bacteria when used regularly. Simply add the rinse to your cat’s drinking water.

With proper preventative dental care at home and professional cleanings, you can help keep your cat’s mouth healthy and breath fresh.

When to See a Vet

Bad breath, discolored gums, trouble eating, drooling, and swelling in cats can indicate serious underlying health issues that require veterinary care. Some signs that warrant an urgent vet visit include:

  • Sudden onset of severe halitosis or foul-smelling breath that smells like urine, feces, acetone, or rotten eggs
  • Gums that appear bright red, pale, blue, purple, white, yellow, or brown
  • Refusal to eat for more than 24 hours
  • Excessive drooling or drooling with blood
  • Swelling of the face, lips, tongue, throat, or gums

According to the Cornell Feline Health Center, “Bad breath, in fact, may indicate conditions from periodontal, kidney, respiratory or liver disease to diabetes, skin disease (involving tissue around the lips) or even cancer.” (source)

Bad breath accompanied by other concerning symptoms like behavioral changes, lethargy, vomiting, or diarrhea also warrants prompt veterinary attention. Do not delay – contact your vet right away if your cat is exhibiting any of these signs.

Cost of Treating Cats with Bad Breath and Black Gums

The costs associated with treating cats for bad breath and black gums can vary widely depending on the underlying cause and necessary treatment. Some potential costs include:

Exam Fees: An initial exam by a veterinarian may cost $50-$250 to assess the cat’s oral health, determine the cause of bad breath and black gums, and recommend a treatment plan. Annual exams thereafter may cost $50 or more.

Cleaning Fees: A professional dental cleaning and polishing by a vet ranges from $300-$800. This may include pre-anesthetic bloodwork, anesthesia/monitoring, and antibiotics.

Extractions: Extracting severely damaged or infected teeth often costs $100-$300 per tooth. Full mouth extractions can cost $800 or more.

Medications: Antibiotics or anti-inflammatory medications may be prescribed post-cleaning at an additional cost of $20-$100.

According to Forbes, cat dental cleanings can range from a few hundred dollars to over $2000. Regular oral exams, dental cleanings, and home care can help minimize costs by catching issues early before they worsen.


In summary, black gums and bad breath in cats can indicate serious underlying health issues. The most common causes are periodontal disease, oral cancer, kidney disease, diabetes, and gastrointestinal problems. It’s critical to get a proper veterinary diagnosis, as many of these conditions can be life-threatening if left untreated. With a timely diagnosis, treatments like dental cleanings, antibiotics, prescription diets, insulin therapy, and surgery can help manage the disease and extend your cat’s life.

While the prognosis depends on the underlying cause, the good news is that with proper veterinary care and follow-up home care, many cats with black gums and foul breath go on to live happily for years after treatment. Don’t ignore these symptoms – bad breath is never normal for cats. Schedule a vet visit right away if you notice these signs, as catching and treating problems early is key. With prompt veterinary attention and dedicated home care, your cat can overcome these oral health issues.

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