Pedigree dogs may be more likely to need pet medication than cross breeds as they are more vulnerable to disease and disabilities.
The RSPCA has said that people need be more aware of this issue and should not buy pedigree dogs based on their looks.
Clare Calder, RSPCA senior scientist, said: "A cute-looking puppy or dog can be hard to resist, but the result of not looking beyond this can be thousands of pounds spent on vets bills and a pet with long lasting health and welfare problems.
"This is one of the biggest challenges facing dog welfare in the UK today."
She added that dogs bred for their looks are “born to suffer”.
A survey by the charity asked people what they associate with pure-breed or pedigree dogs.
They found that the top six responses were: expensive, well bred, from good breeding stock, quality responsibly bred and healthy.
The RSPCA noted that these responses are not always true. Victoria Stilwell, presenter of It's Me or the Dog, said "we have to change", and said we are destroying these animals because of the way they look.