I used the cat version on my cat and he immediately started acting weird. He was running around crazy like and panting. I immediately washed it off of him thinking it was burning or something. He is fine now thank goodness. I will NEVER use this product again and I’m telling ppl I know not to use it either. Spend the extra money and get flea medication from your vet. I’m sorry for anyone else that this product caused any pain or worse for their loved one.