Signs of a sick cat include a change in appetite, bad breath and general change in behavior. Symptoms of cat illnesses can often be difficult to detect, so it's important for owners to watch carefully for any changes in a cat's behavior.
If a cat becomes less affectionate than usual, this could be due to an illness. The same can also be true if a usually independent cat suddenly becomes more affectionate. In either case, a visit to a veterinarian is important, as a cat's behavior is unlikely to change significantly without reason.
Another potential sign of illness in a cat is a change in the smell, color or frequency of feces or urine. An increase in urination, for example, may be a sign of diabetes. If the cat seems to be in pain while urinating, this is also a potential sign of illness.
Bad breath can signify a range of illnesses in a cat. Cats with kidney disease, for example, often develop noticeably bad breath. Diabetes and dental problems can also cause this symptom.
Other symptoms of a cat illness include a reduction in appetite and increased hair shedding. An ill cat may also drink more or less water than normal.