Bad Breath


David McCluggage, D.V.M., C.V.A.

Bad breath becomes more common as dogs and cats age. It is caused by a number of factors, including:

  1. Periodontal disease (bad teeth)
  2. Gingivitis (especially in cats)
  3. Poor digestion
  4. Stomach problems
  5. Chronic small intestinal problems
  6. Poor diet

A veterinarian should examine all animals with halitosis. Teeth should be cleaned if needed. The diet should be modified to improve the quality of the food (see the articles on Feeding Your Dog and Feeding Your Cat ).

Most dogs and cats with halitosis have poor digestion, abnormal bacterial populations in the stomach and small intestines, and often have slow passage of food out of the stomach.

Severe disease involving kidneys, adrenal glands, liver or other organs can cause foul mouth odors. Blood tests would be needed to determine if this is the problem. Animals that eat feces (coprophagia) will have bad breath. Animals that are in the habit of scavenging for garbage and foul tasting plants may develop bad breath, and those that eat indigestible items (sticks, plastic, rubber, etc.) can have bad breath.

Some dogs and cats with bad breath might need radiographs and perhaps endoscopic examination (scoping the stomach) to help determine the problem.

However, most dogs and cats with bad breath do not improve with dentals and don't have systemic diseases. The mouth odor is coming from the stomach and esophagus. Food is not being adequately digested, moving too slowly through the digestive tract, and abnormal bacteria are growing because of this "slugging" of food.

Many animals are given products that mask the odor. We believe that this only hides the symptoms of maldigestion and dysbiosis (abnormal bacteria populations). We recommend that you try to improve digestion, detoxification, and nutrition as primary ways to improve mouth odor.

If the bad breath persists after the veterinary exam and treatment, consider doing the following:

  1. Change the diet to a more healthy one
  2. Supplement the diet with:
    1. Dipan 9 or Similase - digestive enzymes are often very helpful
    2. Douglas Laboratories Multi-Probiotic 40 Billion - beneficial bacteria improve normal bacterial populations
    3. Garlic - aids in digestion and has a healing, beneficial effect to the stomach lining
    4. Aloe vera - heals the mucosal lining of the stomach; click here to read about Aloe Vera
    5. Myrrh
  3. Chinese herbal medicine - often Chinese herbs can heal the abnormal digestive system. Each animal must be individually analyzed for the correct formula. Call for a Phone Consult.