Sometimes a cat will stop using a litter box if there is a new kind of litter that they are not used to. For example if you change from unscented to scented, pine smelling, or just a different texture. Also always keep the box very clean for them which you probably do already.
Nov 04, 2007 Rating
Answer by: Kate
Hi,
These things can come out of the blue and for very little reason. It probably is the fact that she just doesn't like the new litter. The best solution is to give her, her own litter tray and another type of litter. See this page for more info
http://www.our-happy-cat.com/cat-litter-box.html
http://www.our-happy-cat.com/cat-litter.html
I'm sure that your cat will soon get back to her old self once she becomes comfortable with her litter tray routine again. :)