Cats are easier than dogs to get off insulin. You might need to do insulin injections to get the blood sugar back closer to normal if it is extremely high. You must also address any infections in the body because that will also contribute to the high sugar. Research has shown that diabetic cats respond well to a low carbohydrate diet. Stop feeding dry cat food because it is higher in carbohydrates than canned cat food. Avoid the sauce kinds or the ones with rice because those will also be higher in carbohydrates. Purina makes a canned food called DM which works well for diabetic cats which you could start with and then later switch to something else fitting the above description or do a commercially prepared raw food diet that is low in carbohydrates and high in protein.
Also, give your cat Dia-IonX to provide the catalyst for getting the body's enzyme systems working better which will stimulate healing. As you provide the building blocks that allow the body to become more sensitive to insulin you will need to monitor the blood sugar levels so you know when to decrease the amount of insulin or else you might cause the level to drop too low which can be dangerous. If your cat does go on insulin you may be able to gradually wean it off as it needs less and less. If the blood sugar level is not extremely high see what the diet change and Dia-IonX will do for your cat. Many cats will stay under control with just these changes.
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