Healthy Cats

Stomatitis (Sore Mouth) in Cats

Stomatitis is an inflamed, sore mouth, and should be suspected when you see drooling, refusal to eat, difficulty chewing, head shaking, pawing at the face, and reluctance to allow a mouth examination. The inside of the mouth looks reddened, inflamed, swollen, and tender. The gums may bleed when rubbed. Bad breath is present. Lack of self-grooming is evident. Cats may show pain when yawning or opening their mouths to eat.

Cats with any form of stomatitis must be examined by a veterinarian. In some cases, stomatitis is directly attributable to periodontal disease or a foreign object caught between the teeth or imbedded in the tongue. Other cases are associated with an immune deficiency disease such as feline immunodeficiency virus, feline leukemia, feline viral respiratory disease complex, or kidney failure. Cases caused by a specific infection include the following.

Necrotizing Ulcerative Stomatitis (Trench Mouth)

This is an extremely painful stomatitis caused by a bacteria-like pathogen, a spirochete. There is a characteristic offensive mouth odor, usually accompanied by a brown, purulent, slimy saliva that stains the front of the legs. The gums are beefy red and bleed easily. Trench mouth occurs in cats with severe periodontal disease and in those who are run-down because of chronic illness or dietary deficiency. Frontal sinus infection can occur as a complication of trench mouth.  Cats with diabetes, feline leukemia virus infection, or FIV may be predisposed to this disease.

Treatment: Your veterinarian may decide to thoroughly clean the cat’s mouth under anesthesia. This provides the opportunity to treat any decayed roots, loose teeth, and dental calculus. Ulcers may be cauterized with silver nitrate. Infection is treated with an antibiotic. Afterward, the cat is placed on soft, canned food diluted with water or plain broth to a liquid consistency. Aftercare involves daily mouthwashes using 0.1 percent chlorhexidine solution, accompanied by a home program of good oral hygiene.

Ulcerative (Viral) Stomatitis

This is an extremely painful stomatitis in which ulcers form on the tip of the tongue and hard palate. The saliva is clear at first, then becomes blood-tinged and foul smelling. A yellow puslike exudate forms on the surface of the ulcers. Ulcerative stomatitis is seen most often in association with the feline respiratory disease complex, especially calicivirus.

Treatment: It is the same as for Necrotizing Ulcerative Stomatitis, except that antibiotics are not recommended unless the problem is complicated by a secondary bacterial infection.

Yeast Stomatitis (Thrush)

This is an uncommon form of stomatitis seen chiefly when a cat has been on a prolonged course of broad-spectrum antibiotics that alters the normal flora of the mouth and allows the overgrowth of yeast. It also occurs in immunodeficiency states associated with chronic illness. The mucous membranes of the gums and tongue are covered with soft white patches that coalesce to form a whitish film. Painful ulcers appear as the disease progresses.

Treatment: Nystatin and clotrimazole are the drugs of choice. Large doses of B-complex vitamins are also recommended. Ketoconazole may also be used for Candida infections. Correction of all predisposing causes is essential.