Symptoms of Feline Diabetes
"Symptoms of feline diabetes include weight loss, a bigger appetite, increased thirst and an increase in urination. In advanced cases you can see problems with the way your cat walks, lethargic behavior and vomiting."
Once you understand what diabetes does to your cat's body, it is easier to spot the symptoms. While no one knows exactly what triggers the disease, scientists suspect that in cats it usually starts when a feline becomes overweight, is suffering from a problem with the pancreas or is a reaction to Glucocorticoids.
When your cat eats she is taking in proteins, carbohydrates and fats. These three basic foods are broken down by the body into components that are ingested by the cells. One of these component parts is sugar or glucose.
Insulin is produced by the pancreas to help control the rate at which this "energy" is used and absorbed by the cells. When a cat eats too much, or has a pancreatic disease such as pancreatitis (inflammation), the body can't product enough insulin to keep up with food intake. If you have too little insulin due to a pancreatic disease then the body doesn't get enough fuel.
When the body doesn't get enough fuel it looks to fats stored in the body. This is why weight loss is one of the first symptoms.
Without insulin, the glucose or sugar doesn't enter the cells for energy and will start to accumulate in the bloodstream. This triggers an increase in urination and a desire to drink more. As the brain cells become sugar deprived, it triggers the desire to eat more.
Other symptoms which are less common include your cat appearing weak or walking abnormally. This is due to a problem that occurs in the legs and muscles. Chronic or severe diabetes can lead to a disease called ketoacidosis, which is a buildup of acid in the bloodstream. Symptoms associated with this condition are depression, drowsiness, pain in the stomach or abdomen and vomiting.
References:Washington State University
School of Veterinary Medicine