Dr. Bruyette welcomes endocrinology questions from veterinarians and veterinary technicians.
Click here  to submit your question, or send an e-mail to firstname.lastname@example.org 
with the subject line "Endocrinology questions."
Q. How do you manage a cat with hyperthyroidism that is receiving Prescription Diet y/d Feline Thyroid Health (Hill's Pet Nutrition) and is also diabetic?
In the first scenario, if the cat has recently become a diabetic and its hyperthyroidism is being well-controlled clinically and biochemically, I would have the patient stay on Prescription Diet y/d (preferably canned). I would initiate insulin therapy with glargine at 0.5 U b.i.d. along with the diet and would monitor the cat weekly for remission. If the diabetes goes into remission, I would have the owners continue to monitor the diabetes with fasting and four-hour postprandial blood glucose concentration measurements on a monthly basis. If the diabetes does not go into remission after the cat has received glargine and the canned Prescription Diet y/d for two months, I would switch the cat to a higher protein, lower carbohydrate diet and recommend that we manage the hyperthyroidism with either methimazole or radioactive iodine therapy, depending on the owners' preference.
David S. Bruyette, DVM, DACVIM
VCA West Los Angeles Animal Hospital
1818 S. Sepulveda Blvd.
Los Angeles, CA 90025
Veterinary Diagnostic Investigation and Consultation
26205 Fairside Road
Malibu, CA 90256