Diabetes is a loss of control of the amount of sugar in the blood. A cat with diabetes has a very high concentration of sugar in the blood and urine. There are 2 different types of diabetes. The first is insulin-dependent diabetes, where the pancreas does not produce enough of the hormone insulin to regulate the blood-sugar levels. The other form of diabetes occurs when the body does not respond properly to the insulin that the pancreas is producing.

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Diabetes in Cats – Practical Treatment and Care For Feline Diabetes