Thirdly, if you have fleas outside, and your
cat goes
in and out, then you have fleas
in your
house. If you
cat is allergic to fleas and is getting sores from flea bites, then she has fleas and is bringing them into the house. If she doesn't have fleas, then the sores are not from flea bites and are most likely from the flea treatments. Either way the solution is to get rid of the fleas in your house, keep you cat indoors, and stop using flea treatments on her.