Diabetic Cat has Off Days

Careful Evaluation & Dosing are Critical to Success

I have a 14-year-old diabetic cat. She was healthy and stable; her insulin (glargine) dose was 1.5 units. About a month ago she became lethargic and indifferent to food. Her fructosamine test was about 400 and there was sugar in her urine. Her insulin was increased to 2 units. She’s had good and bad days since then but hasn’t completely returned to her normal self. I’m no longer convinced that Prescription Diet m/d is the best for her. There seem to be canned foods out there that are lower in carbohydrate and higher in protein. What should I be looking for?

Dr. Nichol:
When diabetes control is spot-on everybody’s happy but clearly your kitty’s treatment needs adjustment. Behavior changes, like feeling better some days than others, suggests wildly fluctuating blood sugar (glucose) levels. Something significant has changed. There is a long list of possible complicating factors including bladder infection (common in diabetics), dental disease, and disorders of the liver or kidneys. These problems need to be ruled out by a thorough exam along with a serum chemistry profile, blood count, and urinalysis.

Fructosamine tests are a mixed asset; they give us an average of a pet’s blood glucose over the preceding 2-3 weeks but they don’t show its ups and downs throughout a typical day. For that we do a 12 hour blood glucose curve. A drop of blood is glucose-tested every 2 hours with the results plotted on a graph to show how fast insulin and food are absorbed and utilized in a particular diabetic.  This allows greater accuracy in the dosing and timing of insulin and food. Careful management of both is critical to success.

Glargine insulin works well for many feline diabetics. Increasing your kitty’s dose may be just what she needs. But if glargine has lost its effectiveness she can be switched to protamine zinc (Prozinc) insulin.

Finally, diet. There are so many variables with diabetes treatment; we go for simple and reliable every chance we get.  Most of my feline diabetics have done well on m/d (CQ). It’s a highly digestible, consistent product but some cats maintain better on Hills r/d. I urge you to stick with whatever approach works best in your veterinarian’s hands.