First symptom

• The first symptom that is usually visible in diabetic dogs is a sudden fluctuation in weight--either a noticeable gain or loss.
  
  

Water

• A telltale sign is an increase in drinking. Diabetic dogs will often empty water bowls in one long drink and search for more. As a side effect of this, they will often urinate more frequently and in larger amounts.
  
  

Hunger

• As the dog's system tries to balance itself, the dog will often become hungrier than usual, and when left to his own devices will often consume many times his normal food intake.
  
  

Balance

• Dogs may exhibit signs of weakness in the form of shakiness, trembling legs and an unsteady gait.
  
  

Vision

• Dogs may also begin to display vision problems. They may begin to develop cataracts as well, which can occur even if the diabetes is being regulated.
  
  

Frailty

• Dogs in advanced cases may show signs of thinning fur or hair and delicate, papery skin. This occurs when the case is so severe that the dog's body is breaking down its own tissues for the nutrients needed to survive. This is often one of the final stages.