Around twenty percent of diabetic cats can be managed with only dietary modification and hypoglycaemic drugs, reflecting the fact that many feline diabetics suffer reversible insulin resistance. Although several classes of drug have been suggested in the management of diabetes mellitus, only the [[Sulphonamides|sulphonylurea]] '''glipizide''' is widely used for the non-insulin-dependent form. Glipizide acts to increase the secretion of insulin from the pancreatic beta cells and its action is therefore dependent on the presence of functioning beta cells. Possible adverse effects include hypoglycaemia, vomiting, hepatotoxicity with resultant [[Icterus|icterus]]. The response to glipizide is very variable between cats, with some responding well and returning to normal blood glucose concentrations and others showing no response. Glipizide is not a substitute for insulin and most cats will still require insulin therapy.