Medical reasons can be the reason so looking for signs that may tell what the problem is should be the first thing a cat owner does before worrying or even worse shouting at your pet.
If one of your cats stops using the litter tray to urinate suddenly then it could be a sign of a urinary tract infection.
One sign to look out for is if your cat is finding it difficult to urinate and even in pain.
As a litter tray is a small space they often will go outside the litter tray in a larger space to try and make it easier for themselves to go.
Another sign is if they make a noise as if they are in pain when trying to go to the toilet.
Other signs to look out for are blood in their urine and constant licking of the urinary opening.
So before shouting at your cat for being naughty their could be a medical reason for their change in behaviour so a trip to the vets is the best thing for your cat.
Remember cats are not like humans and try and show as little fuss as possible when it comes having a problem.
Other reasons why your cat might stop using their litter tray suddenly is down to cleanliness.
Cats are extremely clean creatures and if a litter tray is too full up then they will find a cleaner place to go.
I mean even a human does not want to use a dirty toilet even if they are the only ones using it! This is also more of a common problem if there are multiple cats in the house.
There should be at least one litter tray to every cat in the house and they should really be cleaned daily and then your cat should have no problem using their toilet properly.
Changing brands of litter may be a cause of the problem as they get use to the feel and scent of a certain type, so trying to buy cheaper litter to suit you might not necessarily suit your cat.
Shouting at your cat will just frighten and confuse them.
They are not evil creatures and are not trying to get back at you for having to move him off your lap or feeding him a few minutes late.
Looking at what may have triggered the change is the best way to find the route of the problem, which without realising could be because of something you yourself have done.
How to help? If you notice any of the signs mentioned above to do with a urinary tract infection take them straight to the vets so they can be treated.
Look at whether anything has changed for example litter or even the location of the litter tray and make sure it is changed regularly enough.
The way I think about it is if I look at the litter trays I have for my cats and I think to myself "I would not go to the toilet in that" then they need changing.
Whilst getting your cat back in his box remember to be patient.
It may take time.
Cats like to go in a quiet, confined location so if you have a litter tray that is open for everyone to see him go maybe consider getting a hooded litter tray which not only gives your cat the privacy they need and deserve but is also great for eliminating odors more.
Robyn Lang Cat Activity Centre