With summer coming, vets are worried about the number of cats they are seeing that have been accidentally poisoned by common flea treatments available in supermarkets.

The Australian Veterinary Association (AVA) is telling cat owners to take extra care when buying flea treatments for their moggy as the weather warms up.

"Some spot-on flea products for dogs available at supermarkets contain a chemical called permethrin," said Dr Mark Lawrie, President of the AVA.

"The treatment is safe for dogs but it's really dangerous when used on cats. People poison their cat by accident - buying a flea treatment they think will cost less and not reading the label properly".

"Our members have started to notice that there are more poisoning cases than previously thought. Some preliminary research is backing this up, and more investigation is underway."

"When a cat is poisoned by this chemical the effect is terrible and there is no antidote. They have trouble walking, muscle twitches, seizures, and high temperature. If not treated they can suffer a stroke and die within hours."

"A flea treatment that people think will save money, can kill cats and end up being really costly for owners, emotionally and financially," Dr Lawrie said.

"It's vital that if the box says DO NOT USE ON CATS, you should heed that warning. If you have a cat and dog you also need to be careful because the risk for your cat, even in  accidental contact with a treated dog, is very high."

"We would really like to see these treatments only made available through vets so that proper instructions could be given to each buyer and cats don't suffer unnecessarily."

"If you have any questions or aren't sure which product to use, talk to your vet," Dr Lawrie said.