Inappropriate elimination is when a cat urinates or defecates outside the litter box in areas such as the furniture or floor. This behavior is messy, unsanitary, and may cause serious damage to your home. If your cat is defecating on the carpet, it may be the result of a serious medical condition, so veterinary assistance may be necessary. Whatever the reason, defecation on the carpet must be stopped, and this is effectively done with consistent training and behavior modification.
Clean the litter box. One of the main reasons cats stop using the litter box is because it is dirty. Like humans, cats want a clean place to use the bathroom. Empty the old litter, clean the box with disinfectant wipes or wash the box, then add new litter. Put the litter box back in the same spot you usually keep it, so your cat knows where to find it. Also, ensure that you have enough litter boxes. One box per cat is a good rule of thumb.
Restrict your cat's access to any area where it has inappropriately defecated. Furthermore, restrict your cat's access to any area where it may inappropriately defecate. Close doors, block off or cover furniture, and keep the cat off countertops. The idea is to keep your cat off the furniture, out of any rooms it doesn't need access to, and to make the litter box the most appealing place to do its business.
Collect any droppings your cat leaves on the carpet and place them in the litter box. This teaches the cat where the droppings belong.
Identify the underlying cause of your cat's carpet defecation problem. Underlying causes may include illness such as a urinary tract infection, anxiety problems, the addition of a new pet or family member, even a change of home or environment. Gradually introduce change to your cat, consider using medication to work through anxiety problems, and get veterinary assistance to resolve any medical problems your cat may have.
Use a spray repellent as an added measure of reinforcement. While some spray repellents are advertised for dogs, they usually work for cats as well. Spray the repellent around any area you want your cat to avoid. Remember to reapply the repellent often for maximum results.