Flea medicine not working

[Digger]

It's the middle of November and I've discovered that my pets are infested with fleas. None of the usual medicines are working like they used to. Has anyone else noticed that fleas and ticks are sticking around longer and that the medicines are no longer as effective? What time of year do these buggers usually stop being a problem?

 

[Pinewood Acres]

It usually takes a few days of a hard frost to kill off parasitic bugs like fleas and ticks. Do the animals go inside your home too? Fleas inside your home will continue to thrive, though, so maybe you should start there. Their eggs will hatch all winter inside your home.

 

[Katie]

I have noticed that spot-on treatment doesn't work as well as it used to, but I don't live in a super warm climate, so I haven't had any problems lately. Even though I spring for the flea treatment that comes directly from the vet, it sure didn't work as well this past year. Maybe the fleas have evolved.

 

[Urban Homestead]

I use Revolution on my cats and it's worked as good as usual. It's never done a great job with ticks though. I live in the South, so it's not unusual for pests to stick around a while. I suspect they'll be gone by December.