Causes of Bad Breath in Dogs and Cats

Laurie Anne Walden, DVM

Photo by Donovan Kelly on Pexels

Bad breath is very common in dogs and cats, but it’s not normal. Unpleasant mouth odor that lasts longer than a day or two warrants a visit to a veterinarian. Bad breath is often the first (and sometimes the only) clue that an animal has dental disease or another medical condition. “Breath fresheners” aren’t likely to work because they don’t treat the cause of the problem.
 
Dental Disease
Dental disease is by far the most common cause of bad breath in dogs and cats. Bacteria in the mouth produce plaque, a sticky biofilm that attaches to tooth surfaces. Within a few days the plaque hardens into tartar. Plaque can be removed by tooth brushing, but tartar removal requires professional cleaning with dental instruments.
 
Plaque also causes gingivitis, or inflammation of the gums. Gingivitis leads to periodontal disease, which affects the bone and other structures holding the teeth in place. Abscesses can form around the tooth roots. Periodontal disease is painful, but dogs and cats often don’t show signs of mouth pain that a human can easily detect.
 
The most obvious visible sign of dental disease is tartar. But animals—especially cats—can have serious periodontal disease without having very much tartar at all.
 
Watch for these signs of dental and periodontal disease in your pets:

• Bad breath: this might be the only sign you can detect at home
• Tartar (hard cream-colored or brown buildup on the teeth)
• Red gums
• Excessive drooling
• Loose or missing teeth
• Reluctance to eat or eating more slowly than usual
• Decreased activity level (general sign of pain in animals)

 
A complete dental procedure for a dog or cat requires general anesthesia; otherwise the procedure would be scary and uncomfortable for the animal. A comprehensive procedure includes oral radiographs, a complete oral examination, probing around the tooth roots, tooth scaling, and polishing to smooth out scratches left by scaling.
 
To prevent painful periodontal disease in your pets, don’t ignore early signs like bad breath. Brush your pet’s teeth regularly to remove plaque before it hardens into tartar. If your pet already has gingivitis or periodontal disease, brushing might be painful, so follow your veterinarian’s recommendations for home dental care. Schedule a dental procedure if your veterinarian recommends it.
 
Foreign Object in the Mouth
String or hair wrapped around teeth, food particles stuck between teeth, sticks wedged across the palate, and other foreign objects are relatively common causes of bad breath in animals. Sedation or anesthesia might be needed for safe removal. Objects lodged in the mouth can cause infection, so animals might also need antibiotics.
 
Skin Disease or Trauma Around the Mouth
Anything that affects the lips, tongue, and other tissues inside the mouth can cause bad breath. Some examples are bacterial and fungal skin infections, electrocution after chewing an electrical cord, jaw fractures, exposure to caustic substances, and cancer involving the mouth.
 
Disease Elsewhere in the Body
Metabolic diseases like diabetes and kidney disease can change breath odor. Respiratory infections produce secretions that lead to mouth odor in some animals. Disorders of the digestive system can also cause unpleasant breath.
 
Eating Something Smelly
Poop is delicious—to some dogs, anyway. Dogs are more likely than cats to eat something disgusting (to a human) or rotten, but cat treats and cat foods can cause pretty strong fish breath. Licking the anal glands can cause anal gland odor from the mouth. For these particular mouth odors, tooth brushing and dental treats might help, assuming your pet doesn’t keep eating the smelly thing.
 
Image source: https://www.pexels.com/photo/black-white-and-brown-long-coated-dog-9623165/

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