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Katzen-artig, Coaching für Katzen und ihre Menschen

This article was written by TOBALIE in cooperation with Katzen-artig, Coaching für Katzen und ihre Menschen

Cats are among the cleanest of pets, often spending a lot of time grooming their bodies and coats. Nevertheless, it is not all that rare for our beloved kitten to become unclean for certain reasons. What are the possible causes of uncleanliness in cats?  What measures can you take to make your cat use the litter box reliably again in the future?

Why does the cat suddenly become unclean?

The causes of uncleanliness in cats are manifold.  About half of the unclean (adult) cats have a physical problem. For the owners it is often not so easy to recognise, because cats usually hide possible pain. 

That’s why the first place to go with a cat that doesn’t use its litter box (any more) should be the veterinary clinic.  It should be urgently clarified whether it is actually uncleanliness or so-called urine marking. These are two completely different areas.

Stress can also lead to uncleanliness in cats. For example, if there are several cats living in the flat who do not get along well or if there is “toilet bullying”. More about toilet management later. 

What are the causes of uncleanliness in cats?

Common causes of uncleanliness can be pain of ALL kinds, for example musculoskeletal disorders, urinary tract diseases/infections, dental diseases and many more. Therefore, as the owner, you should insist on a thorough veterinary examination (bladder ultrasound, blood test, urinalysis, palpation, etc.).

As soon as your pet starts to be unclean, please seek professional help as soon as possible! The longer the cat uses other places than the litter box, the more difficult it is to get rid of this behaviour.

What reasons can be ruled out:

Impurity in cats never occurs because of jealousy, because of a protest action or even out of pure malice. Cats show a behaviour because it is better or more pleasant for them. This behaviour is not directed against anyone or anything!  So your cat is not doing you any harm!

However, this does not exclude fear or frustration. An example: Cats associate pain with the place where it occurs. So if it hurts in the litter box, the cat will look for another place to urinate, such as carpets, blankets, towels, bathroom mats, etc.

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What to do if cats urinate everywhere?

Besides checking with the vet, the most common mistakes are in the litter box. Often, the house cats do not agree with the conditions of the litter box. Among the most common mistakes are:

  • The toilet, the bowl is too small.
  • Not clean enough.
  • Unsuitable place.
  • Too few litter boxes in different locations.
  • Toilets that are not species-appropriate: Hooded toilets, toilets built into a cupboard, hop-in toilets.
  • Unsuitable cat litter: With added perfume, sharp-edged litter that stings the paw pads when scratched, for example silicate litter.

This is what optimal litter box management looks like

In most cases, it is enough to change something in the given conditions. The undesirable behaviour can usually be stopped by small changes and optimisations:

  • Always have one more litter box than there are cats in the household.
  • At least 50 x 70 cm in size and open (commercially available litter boxes are usually much too small!).
  • Low entrance and higher side walls.
  • Cat should be able to turn around and dig comfortably.
  • Fill the litter sufficiently deep: Approx. 5 – 10 cm.
  • Ideal: Back support and free view to the front.
  • Do not place them directly next to each other.
  • In quiet undisturbed places.
  • At least one litter box per floor in the house.
  • Fine clumping cat litter without fragrance additives.
  • Clean litter trays at least once or twice a day.

Do not use cleaning agents containing chlorine or ammonia for basic cleaning of the litter boxes. It is better to use a neutral cleaner or 70% alcohol from the pharmacy. Do not forget to rinse well afterwards.

Enzyme cleaners (Biodor) are very good for removing odours from peeing areas outside the litter tray. 

If you have further questions about this topic or if you would like to get behavioural therapy tips, you can always contact a cat trainer.

Katze am Katzenklo


Most uncleanliness problems in adult cats can be eliminated with proper veterinary treatment, litter box management changes, patience and respect for the cat’s needs.