One can give DIA-IONX along with insulin. I would give 10 drops twice daily with Breakfast and supper. DIA-IONX was designed to help with the symptoms of diabetes and to stimulate the body to heal. Healing takes time and so you need to monitor blood glucose levels to determine if it is appropriate to adjust your therapy. In the cat there are factors that help them to respond well to therapy. It is important to feed wet cat food and no dry food at all if possible and all foods including treats should consist of ingredients suitable for a diabetic. There are some OTC foods that are low in carbohydrates in case your cat does not like prescription diabetic food. I would try these Low carbohydrate canned foods that are nonprescription; they include Friskies Classic Pate Salmon, Fancy Feast - Savory Salmon Feast, Turkey and Giblets Feast, and White Meat Chicken Florentine. These are 2% or lower in carbohydrates. Dry cat food stresses out the pancreas. In addition I give probiotics and Omega 3,6,9. DIA-IONX helps the body to better utilize the diet and supplements better for a synergistic effect for faster healing. Sometimes cats are able to control their glucose levels by diet and supplementation. It is also important to avoid giving water that contains chlorine and fluoride.
Exercise helps to move glucose from the blood stream into the muscles helping to regulate the blood sugar levels. Hopefully you can get your cat to play. Having a consistent schedule is necessary in good regulation.
I do not know if your pet insurance company will cover homeopathics and supplements. You would need to check with them.