A family pet is lucky to be alive after being poisoned by flea treatment.

A Whakamarama family, who want to remain anonymous, feared the worst for their cat, Dexter, when he had a bad reaction to a flea treatment which was designed for dogs.

Shortly after being treated Dexter suffered uncontrollable tremors and was close to death. He was taken to Te Puna Vets where he was treated by vet Kate Heller, who last August saved a cat by giving it a transfusion using blood from a dog.

The latest incident has prompted a warning from Ms Heller about following warning labels and instructions on flea treatment packaging. She said fleas were a constant summer threat to animals, but owners needed to ensure the products they were using were suitable for their pet's size and breed.


"The owners were trying to do the right thing by treating their cat's fleas, but unfortunately they used an old product that had been bought from the supermarket to treat a large dog," Ms Heller said.

"Not all flea products are the same and those made for dogs containing a permethrin base are toxic to cats and can cause severe muscle twitching and eventually seizures and death."

Dexter, an 8kg tabby cross, started going downhill about 18 hours after he was given a single dose of the treatment for dogs. As soon as his family found him shaking uncontrollably they took him for emergency treatment.

Ms Heller said Dexter was experiencing classic signs of permethrin poisoning - facial twitching, rigidity in his legs and a rising temperature.

"There are no specific antidotes for this type of poisoning. All we can do is treat the symptoms and provide supportive care until the cat's body has processed and got rid of the toxin," she said.

Dexter was heavily sedated for about two days and given fluids intravenously to keep him hydrated.

"We had to monitor his temperature closely and continue to top up his sedation throughout the night as the tremors were persistent.''

Dexter suffered uncontrollable tremors and was close to death
Dexter suffered uncontrollable tremors and was close to death

Ms Heller said Dexter was lucky he was a very large cat. "Had he been smaller, the toxic overdose could have been fatal."


She said during the heat of summer flea numbers increased more than any other time.

Dexter's owner said she wanted to share her story with other pet owners to help them avoid making the same mistake.

"There's nothing worse than being invaded by fleas. You just want to get rid of them and we innocently thought any product would do. We didn't realise using the wrong one could have the effect it had on Dexter. We've learnt a very valuable lesson."

She said the family didn't expect him to pull through and took him home from the vet to say their goodbyes.

"It was quite heart-wrenching to see him fitting. We knew the vets had done everything they could for him so we took him home so we could all be with him. But when he came in through the door his head lifted and he began perking up.

"For the sake of saving a few extra dollars and not using the right flea treatment, we almost lost him."

Treating fleas

• Animals need to be treated all year round.

• When buying flea treatment always read the labels and follow instructions.

• Never use a product with permethrin on your cat. Although these products have a wide margin of safety for dogs, they can be toxic to cats.

• Observe your pets after they are treated to spot any adverse reaction.

• Use flea bombs or environmental sprays to keep your house and furniture clear of fleas.

- Tauranga Vets