When cats become older maintaining their body's hydration becomes very important. Always have an ample supply of fresh water available for your senior cat to cleanse impurities and allow for good circulation in the blood. Water is especially important because kidney disease is so common in older cats.
   Sometimes its hard to get your older cat to drink water. You can then ask your vet to give your cat fluid injections in a process called "subactaneous administration". In this process the veterinarian will inject fluid beneath your cat's skin so it can be directly absorbed by the blood vessels.