Soiling and not using a litter tray are problems that many cat owners sometimes face with indoor cats. Sometimes this can be a sign of illness and a visit to the vet might sort out the problem .It could be the cat is suffering from a bladder problems or constipated and so it begins to associate the litter try with pain. Many times indoor cats could be allergic to a food or some chemicals in the home, carpet, shampoo or paint and the explanation may be quite simple. In other cases your cat may be asking for the litter tray to be changed more often or it may be unhappy with the litter being used. Try a finer grained litter or stop using those with a deodorant added. Other possibilities are that the tray is placed too close to the cat’s food or in a high traffic area where feet constantly tramp past. If lack of peace and privacy could be the problem, a hooded litter tray may be the solution.
Never smack or scold an indoor cat for soiling, even if you catch it in the act: this will increase any feelings of insecurity and make the behavior worse. The old idea of rubbing the cat’s nose in it is even more counterproductive; the cat might enjoy the smell and want more! Begin by cleaning the area with a warm solution of biological detergent, followed by surgical spirit or a weak solution of household bleach and a scattering of baking soda. Check your fabrics for colour fast first!!
Do not use any disinfectant containing chlorine or ammonia; it may smell clean and fresh to you but to a cat it smells as though another cat has been in the house and draws it back to that place. Some disinfectants can also be absorbed through the paws.
Discourage the cat from revisiting the soiled area by laying a sheet of slightly crinkled aluminium foil over it or try feeding the cat in that place, once it is completely clean. No cat will soil its feeding place. If the cat tends to leave a deposit in the middle of your bed-this seems to be a favorite location for an indoor cat- if the cat is upset at being left alone or left behind while the family goes on Holiday-fix a sheet of plastic over the bed. Remember that once your understand why the cat is soiling its usually easy to rectify.