• Excessive drooling can occur in any dog.dog image by Zbigniew Nowak from Fotolia.com
  
  Excessive drooling is known as hypersalivation. Hypersalivation is a common part of canine companionship because it can occur due to nervousness, fear, anxiety or even the anticipation of being fed. However, drooling that begins without a known cause can be an indication of a health issue. Bring dogs that are displaying unusual or excessive drooling to a veterinarian for evaluation.
  
  

Bloat

• In dogs, canine bloat is a serious, life-threatening health issue that requires immediate medical attention. While bloat may not always be immediately obvious to the owner, one warning sign of bloat is unusual or excessive drooling.
  
  

Dental Diseases

• In many dogs, the mild to intense pain that is associated with periodontal disease can lead to drooling. This includes issues such as an abscessed tooth, tooth loss or stomatitis (inflammation of the mouth interior).
  
  

Distemper

• Canine distemper is another serious disease that can lead to excessive drooling in some dogs. Dogs with distemper may also have coughing, diarrhea, vomiting and nasal or eye discharge.
  
  

Heat Stroke

• One common cause of excessive canine drooling is heat stroke. Heat stroke is a serious health issue and requires immediate treatment to prevent further damage. Additional symptoms of heat stroke in a dog include vomiting, rapid breathing, red or pale gums, diarrhea and shock.
  
  

Liver Disease

• Various diseases that affect the liver can lead to the production of excessive drool in a dog. Take older dogs that are prone to developing organ-specific disease to a veterinarian immediately if they begin drooling excessively.
  
  

Mouth Ulcers

• In dogs, mouth ulcers can be the result of many different issues: kidney failure, ingestion of poisonous chemicals, bacterial infections or electrical cord burns. Mouth ulcers, no matter what their cause, can lead to excessive drooling in the affected dog.
  
  

Rabies

• As expected, dogs that become infected with rabies may begin to produce excessive amounts of drool, along with other symptoms such as fever, aggression and other unusual behaviors.
  
  

Toxins

• Various toxins that the dog may have come into contact with or consumed during the day can also lead to unusual drooling. These include antifreeze, chocolate, mothballs, mouthwash, batteries and various detergents.
  
  

Tumors

• Much like an ulcer, tumors located in the mouth can lead to unusual drooling in the affected dog.