Cats hide illness well, so subtle changes can signal serious problems. Seek same-day or emergency care if your cat cannot urinate, especially males, or if you see straining with little output. Labored breathing, open-mouth breathing at rest, sudden paralysis, seizures, major trauma, or suspected toxin exposure are also emergencies.

Repeated vomiting, especially with lethargy or refusal to eat, warrants prompt veterinary attention. Cats that go without food can develop hepatic lipidosis. Blood in urine or stool, severe diarrhea, or a painful, distended abdomen need evaluation without delay.

A cat that hides constantly, stops interacting, or shows a marked change in thirst or litter box habits should be seen soon, even if the signs seem mild. Weight loss, poor coat, and bad breath can indicate chronic disease that progresses if ignored.

Wellness visits help establish baselines: many veterinarians recommend annual exams for healthy adults and more frequent visits for kittens, seniors, and cats with chronic conditions. Dental disease, arthritis, and kidney issues are common in breeds of all sizes but may show up earlier in some individuals.

Trust your instincts. If behavior or appetite is off for more than a day, calling your clinic for triage advice is reasonable. Early treatment often costs less and improves outcomes than waiting until a crisis.