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Last updated January 1, 2014

Ulcerative Stomatitis (Mouthrot) in Reptiles

Melissa Kaplan and Robert Jereb DVM, Journal of Wildlife Rehabilitation 18(2):13. 1995


Note: This article was written for wildlife rehabilitators who, while they have specialized training in working with many types of birds and mammals, generally have little training or experience working with reptiles. Many are trained to perform certain levels of veterinary care on the animals they take in, and all work closely with veterinarians experienced in the care and clinical management of wildlife. This document is not meant to serve as a "do it yourself" manual for the herper who is not trained in the procedures described and who does not have access to appropriate veterinary care, antibiotics, etc.


Stomatitis, or mouthrot, as it is commonly referred to by herpetoculturists, is a symptom of systemic infection in reptiles. Noted for a wide variety of symptoms, it typically presents as cheesy yellow or yellowy-gray plaques in the soft gum tissue in the mouth, with erythema and increased salivation. Stomatitis is a secondary infection. The mouth must be treated and the animal started on a regimen of appropriate systemic antibiotics. The animal's environment should be modified as necessary to aid in recovery.

Keywords: Stomatitis, mouthrot, bacterial infections, reptiles, ulcerative stomatitis


Stomatitis is most commonly seen in snakes and lizards, with less frequent occurrence in chelonians. Early symptoms may be subtle and often overlooked: slight petechia; inappetence, a reluctance to feed or change in food selection; and increased, thickened, ropey or sheeting saliva. In cases of sudden and severe onset, there may be acute inflammation of the buccal and pharyngeal membranes or gingival necrosis. Pockets of caseous yellow, yellowish-gray or white-gray pus may occur in the soft tissues. Left untreated, the condition may progress to osteomyelitis of the mandibular and cranial structures. In advanced cases, the head may be quite swollen. Teeth may be found loose within the necrotic tissue.

A variety of organisms have been associated with stomatitis, such as Aeromonas aerogenes, A. aerophila, A. hydrophila, Citrobacter freundii, Proteus sp., Pseudomonas aeruginosa and P. fluorescens, Staphylococcus sp., and Streptococcus. Other bacteria, such as Mycobacterium chelonie and the anaerobic Clostridium sp., have also been found in these lesions and exudates.


Before the appearance of modern antibiotics, diverse substances were used to wash out the buccal cavity: vinegar, hydrogen peroxide, feminine douche products, iodoform and a variety of patent medications. Some of these worked to a certain degree in that they altered the environment of the mouth to make it less desirable for many of the organisms. Some of these products are, however, cytotoxic and have fallen out of use in favor of less destructive preparations and systemic antibiotics.

Dilute solutions of povidone-iodine (Betadine®) and chlorhexidine diacetate (Nolvasan®) are two products with low cytotoxicity. There are a variety of objects used to dislodge and remove the plaques from the mouth, including dulled dental curettes, small bone curettes, needle-nose serrated tweezers, and cotton-tipped swabs. In a pinch and when nothing else is at hand, the jagged end of a broken cotton-tipped swab shaft is useful.

Care must be taken to prevent accidental aspiration or ingestion of detritus when flushing the mouth. The reptilian glottis is high up in the mouth at the base of the extremely agile tongue; in snakes, it is close to the front of the mouth. To this end, the reptile should be laid on its side or held with the head tilted towards the ground.

Flush the mouth with the dilute solution of 1% povidone-iodine or a 0.25%-0.5% solution of chlorhexidine diacetate.[1] Debride using the curettes or tweezer. The resultant cavity must be checked to ensure removal of all the material. Any loose detritus should be swabbed away with a swab dipped in the dilute solution. Once the plaques are removed, the mouth should be flushed again. The animal is then started on a course of antibiotics. (See Table 1.)

During the course of the antibiotic therapy, the mouth should be checked daily to watch for any recurrent plaques. It is not unusual for the above process to be repeated two or more times during recovery. Particularly severe cases may require more than a single treatment on the first day or two.


If there is copious bleeding upon the removal of the first plaque, the animal may be started on a 10 day course of antibiotics. This encapsulates the plaque and reduces vascular activity immediately around the site.


Resistant Infections
Reptiles have a variety of Gram negative and anaerobic bacteria. While they may not be the underlying cause of the stomatitis, their existence may impede recovery. The presence of such bacteria may require that two antibiotics be administered simultaneously.[4]

Most veterinarians and rehabilitators begin with a broad-spectrum antibiotic, but these may not be effective due to the causal organisms and the degree of patient debilitation. The standard culture sampling techniques of swabbing or washes may a yield a confusing mixture of natural and opportunistic buccal and environmental flora. A better method for obtaining a sample for culturing in resistant stomatitis cases is to make a incision into the infected gum and take a small sample of the infected tissue.[3]


Stomatitis in Chelonians
Incidence of stomatitis in chelonians occurs with less frequency than in lizards or snakes, but when it does it can look quite serious. Most, however, are easily resolved when caught early enough. In one reported case, despite the apparent successful treatment with oxytetracycline, the hard palate was perforated as a result of diphtheritic ulcers on tongue and palate.[1]

Simple stomatitis in chelonians may be treated by thorough washing of the buccal cavity with dilute povidone-iodine solution, finished by an application of topical antibiotics. Systemic antibiotic therapy is generally not required.

In severe or resistant stomatitis in chelonians, cultures should be done to identify the primary or any secondary organisms that may be at work and parenteral antibiotic therapy should be initiated.


Supportive Therapy
Reptiles suffering from stomatitis often cease or greatly reduce voluntary intake of food and water. Supportive therapy should include replacement of fluids (15-20 mg/kg q 24 hr) and administration of vitamin B-complex (0.25-0.75 mg/kg) and vitamin C (10-20 mg/kg daily).[1] Vitamin A may also be supplemented with care given to administer only very small doses due to potential toxicity. If the patient is going to be tube-fed, vitamin A should be given orally, mixed in with the food.

If the patient has not eaten in some time and feeding is indicated, whole prey should not be given. Force feeding whole prey is stressful under the best of conditions; given the intensive curetting some patients require, additional stresses should be minimized as much as possible. Instead, puréed prey or a nutritional slurry should be administered by gastric tube. (See Table 2.)


Reptiles should be kept at temperatures near the upper end of their required temperature gradient to ensure maximum benefit from the antibiotics and to boost their immune system function. Reptiles who would otherwise have temperatures dropped at night should be kept at their daytime gradients. Heat should be supplied according to the nature of the animal (thigmotherms require warm surfaces to lie upon or against; heliotherms require overhead basking lights). If heliotherms require supplemental heat at night to keep temperatures in the optimum range, it should be provided by an undertank heating pad, a special nocturnal heat light, or a ceramic heating element that emits no light. White light should not be used at night as it disturbs both diurnal and nocturnal animals.

The enclosure should be set up to reduce stress. Hide boxes work well for burrowing and cave-dwelling animals. Arboreal animals should be furnished with a secluded branch on which to lay. The enclosure should be screened from high levels of activity.

Water should be supplied in a form that can be utilized by the animal. Many small lizards require droplets to lap. A drip bottle can be set up over a clean plant or rock, or the sides of the tank may be misted with water at least once daily, taking care to not over-saturate the enclosure. Other lizards, snakes and chelonians do well with a shallow bowl of fresh water.



Frye, FL. 1992. Reptile Care: An Atlas of Diseases and Treatment. TFH Publications, Inc., Neptune City NJ. pp. 111, 116-117.

Boyer, TH. 1994. "Emergency Care of Reptiles." In Seminars in Avian and Exotic Pet Medicine, 3(4):210-216. AM Fudge DVM and J Jenkins DVM, eds. W.B. Saunders Company, Orlando FL.

Mader, DR. 1993. "Common Reptilian Bacteria: What are they and what is their significance." The Viviarium 4(6):27-29.

Stahl, SJ. 1995. "Bacterial Diseases." Journal of the League of Florida Herpetological Societies, May 1995, pp. 17-19.


Betadine® (povidone-iodine), The Purdue Frederick Company
Hill's a/dTM, Hill's Pet Nutrition, Inc.
Nolvasan® (chlorhexidine diacetate), Fort Dodge Laboratories
Silvadene Cream® (silver sulfadiazine), Marion Laboratories


Table 1. Parenteral Antibiotics



Amikacin (Amiglyde)

5 mg/kg SQ, IM then 2.5 mg/kg q 72 hrs (snakes);2.25 mg/kg IM q 96 hrs (alligators)


200 mg/kg IM q 48 hrs (tortoises)

Ceftazidime (Fortaz)

20 mg/kg IM q 72 hrs (snakes)

Enrofloxacin (Baytril)*

5 mg/kg PO, SQ, IM q 24-38 hrs; 10 mg/kg PO, SQ, IM q 24 hrs for resistant infection

Gentamicin (Gentocin)

2.5 mg/kg IM q 72 hrs (snakes)


6 mg/kg IM q 72-96 hrs (red-eared slider)


100 mg/kg IM q 48 hrs (pythons)

* = May cause tissue necrosis at injection site, especially if administered SQ; dilute with lactated Ringer's, sterile saline or bacteriosstatic water prior to injecting. Injectible enrofloxacin (Baytril) may be given orally.


Table 2. Nutritional Slurries Ingredients


Hill's a/d thinned with Pedialyte®, 1:1 solution of Gatorade and water, or plain water.

Omnivore I

Equal amounts of Hill's a/d and baby food vegetable, thinned with Pedialyte, 1:1 solution of Gatorade and water, or plain water.

Omnivore II

Herbivore slurry mixed with equal parts Hill's a/d, thinned with Pedialyte, 1:1 solution of Gatorade and water, or plain water.


Soaked alfalfa pellets, pureed squash, pureed fruit, reptile multivitamin, and reptile calcium supplement, thinned with Pedialyte, 1:1 solution of Gatorade and water, or plain water.


Melissa Kaplan
Reptile & Environmental Education
POB 366
Fulton CA 95439

Robert Jereb, DVM
North Park Veterinary Clinic
5700 State Farm Drive
Rohnert Park CA 94928
(707) 585-2899

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