Resistant Fleas
 

There is some evidence, especially in the Northeast and Mid-Atlantic regions that some species of fleas are becoming resistant to some Fipronil-only topical flea medicines. Add to this the unusually warm and wet summer and fall, flea infestations are becoming common even in households where all pets are treated.

a) Do check your pets regularly for fleas and other parasites. You may also place a shallow dish containing soapy water under a night-light and look for fleas each morning.
b) Do consult with your vet on whether there is heavy flea activity in your area.
c) Do consider "Plus" type topical medicines that add a supplemental chemical to the basic Fipronil.
d) Do treat every month whether you think you need it or not. One single day above 45 F is enough.
e) Do note that fleas (and other parasites) will travel into your domicile on shoes, clothing, through even the finest window screens, on other animals, and by any of several other routes such that "indoor only" is, effectively, meaningless.
f) Note also that even if you keep your domicile at very low humidity (under 50%), if fleas actually get onto your pets, ambient temperature and humidity is also meaningless.
g) And, if also have dogs, as we do, consult your vet on their proper treatment as well. They do (or should) go out, and they are constantly exposed to parasites, whether you see them or not.

Remember: CONSULT YOUR VET on the conditions and best options where you are.. Do not rely on anecdotal information, do not rely on "the internet" to make your decision for you.