Spitting up froth, or foaming at the mouth, used to be a tell-tale symptom of canine rabies. However, in areas where regular rabies immunizations are common, the vaccinations greatly reduce the deadly disease. Many dog owners now attribute foaming at the mouth to be a classic symptom of some gastrointestinal problem, such as acid reflux. While foaming at the mouth may occasionally indicate acid reflux, there could be other reasons for this symptom.
Acid Reflux Symptoms
Knowing the symptoms of acid reflux can help dog owners to understand -- and rule out -- what may cause their dogs to foam at the mouth. An uncontrollable reverse flow of gastric (intestinal) fluids into the tube between the throat and the stomach causes acid reflux. Symptoms include regurgitating food, pain while swallowing, loss of appetite, weight loss, fever, and extreme salivation. Younger dogs and dogs with congenital hiatal hernias are prone to developing the problem.
Foaming at the Mouth
While foaming at the mouth may indicate canine acid reflux, there are other reasons for this problem. Dogs who overexert themselves in play or exercise, or those who develop a bad taste in their mouths may foam. Nausea, stress, certain types of poison, and oral health issues such as abscesses or tooth injuries also cause foaming. More seriously, seizures and rabies can present with foaming, so immediate veterinary attention is necessary if you notice the symptom.
Diagnosing Acid Reflux
No matter how much or how little your dog foams at the mouth, a trip to the vet's office with your pup in tow is really the only way to determine the cause for this symptom. Your vet may decide to do an esophagoscopy exam, which uses an internal camera to go in and view the lining of the esophagus. The vet might find it damaged or bleeding due to your dog's regurgitation.
Treating Acid Reflux
Most vets recommend dietary changes to help control gastrointestinal problems like acid reflux. After withholding food for a day or two under a vet's instructions to allow the lining to repair itself, give your pup small and frequent feedings of low-fat, low-protein meals. Reducing fat and protein is important because dietary fat weakens the muscle between the stomach and esophagus -- allowing food to regurgitate -- and protein increases gastric acids in the stomach. Some vets may also prescribe medication.