Jonathon's blood sugar wasn't just a spike!

Jonathon's blood sugar has now been in the 200's for three days.  For the last month, it was between 73-131.  I called the vet Tuesday and she said that we might have to put him back on insulin.  We haven't done it yet, but I see it in our future.  Yesterday morning his blood sugar was 299, last night it was 306!  I feel bad for him because I have to test him frequently and his little ears are sore.

The vet said she is concerned but not overly concerned about his blood sugar because it fluctuates.  I don't understand how it can be so high after it was between 73 and 131 for the last month.  I looked online at a chart showing the blood glucose curves for humans.  It shows definite spikes in blood sugar after meals-but it goes back down.  It is not high for days.  He has been eating some of the other cat's food, which is high protein, low in carbs but the vet said he should not be reacting to it with high blood sugar.  He eats Science Diet, which is high in carbs.  (At night and when we are not home, Jonathon stays in his room, away from the other cats and their food.  When he comes out with the other cats, he sometimes eats their food.)  Hopefully, this is just a phase and it will stop.  I don't know if that is possible but it would be nice.

If he were on insulin still, these blood sugar levels would be good.  We would aim for them but because he is not on insulin, it is a little concerning.