Many animals are at risk of needing pet medication because their owner has not had them vaccinated.
According to Ros Davies, cattery rehomer at Battersea Dogs & Cats Home's London site, most people do not bother vaccinating cats and a high percentage of cats have still not been neutuered.
She said: "Owners need to take real responsibility for their pets, which means neutering, vaccinating, michrochipping and making sure your cat has a collar and tag."
Ms Davies said microchipping is important when it comes to reuniting lost pets with their owners. Despite this, 95 per cent of the cats brought into Battersea were not chipped.
Cats Protection recently warned owners about the importance of neutering their pets at an early age.
The charity said we should get cats neutered at four months rather than the traditionally recommended six months, as this would help to reduce the number of stray and unwanted litters.