For what it is worth, I have been using Frontline spray with my ferrets for 7 years and have experienced no negative effects on my ferrets nor myself by handling them or administering it. Personally, it is the my flea control product of choice. Also, I have been told to use it for earmites, but I prefer ivomec for ear mites and heartworm protection. Julie Julie Fossa (772)228-9067, temp. West Central Ohio Ferret Shelter http://www.wcofs.org International Ferret Congress http://ferretcongress.org/ [Posted in FML issue 4837]