My 13 year old Calico has decided not to use the cat box periodically a few years ago, now it is all the time. What can I do, she seems to me healthy, eats, drinks and hasn't changed her personality. What can be the cause if nothing's changed in the house, her box had been in the same place for 11 years.
This could be a medical or a behavioral problem. First, she needs to be screened by your vet for a medical problem. If it turns out to be behavioral then I recommend that you buy another litter box. This provids more options, especially if she is feeling the effects of age. You can also try Feliway. Feliway is a calming phermone spray used for inappropriate marking. vetcare