Fleas and Stronghold not working, what next?

[lollilou]

We have two cats, they have been treated about two weeks ago with Stronghold which has always worked in the past. Not this time they both still have them. What should we use next? Can we treat now or would that be too soon after the last treatment. Really need to get rid of the buggers my dds legs are covered in bites! Tia.

[Fluffycloudland77]

Advocate? Different active ingredient.

A program injection is worth considering, it doesn't kill fleas but it stops them breeding so the house doesn't get infested.