1Inappropriate elimination A cat that urinates inappropri- ately could have any number of conditions associated with the behavior, including lower urinary tract disease, kidney disease, uri- nary tract infection, and diabetes mellitus. It can also be a sign of arthritis, which makes it difficult for cats to get into the litter box.
2Changes in interaction Cats are social animals, so changes in interactions with humans or pets can signal disease, fear, anxiety, or pain.
3Changes in activity
A decrease in activity is often a sign of arthritis or systemic illness, while an increase in activity can be caused by hyperthyroidism.
4Changes in sleeping habits
If your cat is sleeping more than normal (keep in mind that average adult cats may sleep 16 to 18 hours a day—though much of that is “catnapping”), it could be a sign of an underlying disease.
5Changes in food and water consumption Most cats are not finicky eaters. Decreased food intake can be a sign of several disorders, ranging from poor dental health to cancer. Increased food consumption can be caused by diabetes mellitus, hyperthyroidism, or other health problems.
6Unexplained weight loss or gain Sudden weight loss can be a sign of hyperthyroidism, diabe- tes mellitus, or a host of other diseases. Obesity, on the other hand, can cause an increased risk of diabetes mellitus, joint disease, and other problems.
Patches of hair loss or a greasy or matted appearance can signal an underlying disease. Cats who
have difficulty grooming often suffer from fear, anxi- ety, obesity, or other illnesses. An increase in groom- ing may signal a skin problem.
Signs of stress
Stressed cats may exhibit signs of depression,
hide more, or spend more time awake and scanning their environment. These signs may indicate a medi- cal condition, so it’s important to rule out physical ailments before addressing the stress behaviorally.
Changes in vocalization
An increase in vocalization or howling is often
seen with an underlying condition like hyperthyroid- ism or high blood pressure. Many cats also vocalize more if they’re in pain or anxious.
Bad breath is an early indicator of an oral problem—studies have shown that 70 percent of cats have gum disease as early as age 3.
Adapted from healthycatsforlife.com and Dr. Susan Little, DABVP (feline), Bytown Cat Hospital in Ottawa, Ontario