From the study on FD I was reading today, re:meds like glipizide...
“Oral hypoglycemics may be used in human type 2 diabetes patients with sufficient endogenous insulin secretion to maintain euglycemia without insulin therapy. Sulfonylureas and meglitinides stimulate insulin secretion from pancreatic β cells.
82,
83 However, the majority of diabetic cats have insufficient β-cell function to achieve good glycemic control using these alone.
30,
84Similarly, biguanides such as metformin require functional β cells and sufficient circulating insulin to be present if they are the sole therapy.
85 In five newly diagnosed diabetic cats treated solely with metformin, only one cat had measurable serum insulin concentration pretreatment, and this was the only cat that achieved good glycemic control.
86 While α-glucosidase inhibitors such as acarbose can slow intestinal glucose absorption and reduce peak postprandial glucose concentrations, they are minimally effective in cats eating multiple small meals.
85,
87 The trace element vanadium supplemented at 45 mg/cat/day improved glycemic control in diabetics treated with PZI insulin, with a mean insulin requirement of 3 U in vanadium-supplemented cats compared with 5 U in cats treated with PZI alone.
88
Insulin treatment is associated with a higher probability of achieving glycemic control and eventual diabetic remission, compared to the sole use of oral hypoglycemic agents, and this continues to be the recommended treatment for diabetic cats.”
From here:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6053045/
The whole article is good and may be nice to bring to your vet, but it sounds like you finally found a vet who has some sort of clue, at least on this one issue.
