Apparently "Advantage" is NOT totally safe. A person on the dog mailing list reported that her bloodhound experienced hind end paralysis shortly after the owner applied "Advantage." There were no other environmental changes or other related factors involved. The owner had used "Advantage" on the bloodhound and on her other dogs with no problems. The vet reported it to the manufacture. It took about 3 days for the dog to recover. I wonder if some of the cases of hind end weakness on ferrets can be traced to "Advantage"? Nan and SuperSnooper [Posted in FML issue 4012]