If your cat is repeatedly straining with little, no, or uncertain urine, call an emergency veterinarian immediately; do not wait to change the litter setup. Our litter-box straining guide explains what to share with the clinic without delaying care.
Has the route changed since a new cat arrived?
Look beyond fighting. The Feline Veterinary Medical Association describes subtle tension such as prolonged staring, stalking, cornering, or occupying a doorway that blocks a resource. Provide separate essential resources and safe resting places; use gradual introductions rather than forcing the cats together. Persistent tension needs veterinary advice, including assessment for pain or illness.
Compare an ordinary moment before and after the arrival: does your older cat still reach the same meal, water, litter box and bed? Note the place, the other cat's position and what the older cat actually did. A fictional note might read: “At breakfast, the new cat sat in the kitchen doorway. Milo turned back and ate only after the doorway cleared.”
A new household member does not establish the cause of a health change. Tell your veterinarian about changed eating, litter habits or activity. Our vet visit checklist helps organize the observations you already have; do not wait to finish it before seeking care.