Instruct: Classify Amazon reviews into positive or negative sentiment
Query: POISONING PETS

DO YOURSELF A FAVOR, and check this website before you think about using this product on your pet:[...]This company has been peddling this garbage as a worthy substitute to actual, helpful flea medications, and prolonged use will likely result in the death of your furry friend because of harmful pesticides. I used this on my dog, and within the first hour he had it on, he began vomiting and limping, and wouldn't eat. I had to shave him, bathe him three times, and spend lots of money at the vet to make him better, and that's only because we got lucky and caught it before he was too far gone. If you care at all, you'll just spend a few extra bucks and buy something from your vet that won't result in the premature death of a pet you care a lot about.