Flea Control for CRF Cat

It appears we have a little flea issue moving throughout our house. One of my cats has CRF and I'm at a loss as to what I can/should treat her with. At her last vet visit, her numbers were looking good. She's getting SQ fluids 2x/week and doing really well. When I found out she had fleas, I treated her with Advantage without thinking......that was a bad idea. Within a day after treating her she was much more lethargic and was sleeping in the coat closet (not normal for her). Within about a week she came back around. My guess is that the Advantage was absorbed systemically and her kidneys were not able to filter it properly.

Anyway, what other options are there to treat her fleas? I don't want to use Advantage again. I've been treating our other cat with Advantage with no issues.

All flea medications are essentially poisons. Your best bet right now is to at least talk to your vet about her behaviour since you administered the Advantage.

You can get some Diatomaceous Earth (usually from a garden centre or a place that sells supplies for farmers), food or human grade only, sprinkle it into your carpeting and brush it down into the fibres. Leave it a few days before vacuuming it up. Any fleas that are in your carpeting will die and the DE will kill any new hatchlings.

DE (human/food grade) is completely safe for mammals, i.e., if they should ingest any the only thing that would happen is that the DE would get rid of any internal parasites your pet may have.