Instruct: Classify a given Amazon review as either positive or negative.
Query: Do not use!

First time using this on my dog who has fleas. That same night my wife notice him having behaviors and now he is shaking, has difficulties walking and is inactive and lethargic. I have already contacted the vet the following morning for him to be examined, but in the interim looked online for similar cases with other pet owners. To my suprise, there are lots of them and Seargent's has been all so ever slow to respond to the numerous incidents that have already occurred. So be careful, think twice and go through your vet first.