Any foods specifically not made for cats can cause them problems, but the following are particularly harmful: xylitol, chocolate, raw meat, fish and alcohol, according to petMD. Older cats can also become lactose intolerant in later years. Some of these foods cause temporary problems to the digestive system, but others, such as alcohol, can cause serious long-term damage.
If a cat is showing signs of illness, such as diarrhea or vomiting, and is suspected of having eaten any of the above foods, call a vet immediately, recommends petMD. Alternatives to a vet include the pet hospital and the pet poison helpline. If the cat is very ill, the vet or the pet hospital may keep it overnight to monitor it and take blood samples. In most cases, the vet checks the cat over, perhaps inducing it to vomit, before allowing the owner to take it home.
The easiest way to prevent a cat from eating harmful foods is to keep all the harmful foods locked away in a cupboard. However, this does not mean cat owners cannot give their cats treats. Cats love to eat cooked meat and vegetables, explains petMD. Owners of young cats can also treat them with a bit of cheese.