Major Causes

• Dogs with polydipsia, or the need to drink too much water, are usually sick. Polydipsia is a symptom of many illnesses, including canine diabetes, liver disease, kidney problems, pituitary gland problems and high blood calcium.
  
  

Minor Causes

• Excessive exercise, heat and humidity will also make a dog drink more than usual. Dogs with flat faces will be more affected by the heat than dogs with longer noses. However, once the dog's body temperature cools, so should the dog's desire to drink water. If it does not, see a vet.
  
  

Diagnosis

• Dogs with polydispsia will be given a variety of tests to determine the illness affecting the dog. These include a urinalysis, a physical exam and notes of any other strange symptoms like an increase or loss in appetite; bad-smelling urine or weight loss.