Q2.1. Can I give oral medication instead of insulin?
A2.1. Possibly. You should discuss this with your vet. Oral medications such as glipizide or glyburide will allegedly work for about 30% of diabetic cats. However, because these drugs can cause liver damage (and even further damage to the pancreas), and because giving an injection is often easier than giving a pill, most people on this board prefer insulin. Several people who switched to insulin after using drugs have reported that they thought the oral medication only delayed regulation. Others believe that starting with drugs rather than insulin made it impossible for their cats' diabetes to be controlled with changes in diet alone. Another drug, acarbose, works by blocking or delaying the absorption of carbohydrates from food. It probably is not necessary for a cat who is on a low-carbohydrate diet.
Oral medications are not a good idea for cats with elevated liver values (due to the possibility of liver damage), or ketoacidosis or neuropathy (due to the need to bring glucose levels down immediately). See the Pets with Diabetes site for a more detailed explanation. If your cat shows uncharacteristic lack of appetite, vomiting, lethargy or jaundice, discontinue the medicine and call your vet. You should also have liver enzymes monitored frequently during the early months