Your original thread on Lantus:
Not responding to Insulin
Is the prescription food dry or canned? Neither are good for diabetics. The dry in particular is high in carbs which will keep blood glucose levels high. If it's Purina DM, the DM stands for dietetic management not diabetes management. The ingredients are no different from many cheap commercial foods and the food is expensive. We recommend only feeding low carb canned foods. It's been called the "kitty Atkins" diet. Many commercial brands are suitable: Fancy Feast Classic / Gourmet pates, Friskies, Merrick, Tiki Cat, etc. The food charts are here:
Links to FOOD CHARTS Anything under 10% carbs is best. You can agree to disagre with the vet about food
Home cooked and raw diets are also options.
Diabetics do best with small meals spread throughout the day. Two meals a day leaves a cat too hungry and affects blood glucose levels. Many people use a programmable timed feeder for this purpose.
One thing to note: changing the diet can have a big impact on blood glucose levels so it's important to change the diet slowly and closely monitor blood glucose levels to catch any potential hypo and reduce the insulin if needed. You're using the Libre meter so it should be easy to monitor levels.
There are some conditions that may cause a large amount of insulin to be needed. There's info here:
Sticky - Acromegaly and Other High Dose Conditions: What We Know If after a diet change, your cat still needs a large amount of insulin you should ask the vet about testing for these other health conditions.
What dose of insulin did your cat start at? How often was the dose increased? Lantus is a depot type insulin and needs at least a week for a dose to settle before you can really see how it is working on blood glucose levels. More on the depot here:
Sticky - What is the Insulin Depot?
Tips and tricks on using the Libre:
https://felinediabetes.com/FDMB/thr...s-cgms-for-diabetic-cats.301950/#post-3278600
