Using vinegar spray against fleas, but my cat is licking it off

Hey all,

First time post. My cat is on the elderly side, about 16. She's an indoor cat and we just moved into a new place that is teeming with insects outside (Louisiana), including, of course, fleas. She managed to pick them up and now we've got quite the flea problem; and by we I do mean both her and now me. I've been doing a lot of reading on non-chemical options, things available at the store, etc.

There's a lot I can go into, but I'll keep it straight-forward for now: I just started using vinegar. Last night, after using the flea comb forever (she cooperates and relaxes at first but eventually fights and scratches and jumps), I used a mix of apple cider vinegar and water and just doused my fingers in it and wiped her down, doing the best I could to rub it in beyond the fur to her skin. Tonight I used a mix of distilled white vinegar and water from a spray bottle (cheaper option at the moment). 

My problem is that she spends the next hour licking it off. I don't know if it's useless to continue doing it if that's the case. I mean, she really obsessively licks and licks. And on top of being a useless tool in this war against the fleas, I'm worried that she's ingesting a lot of vinegar that isn't good for her. 

Anyone have any insights? How is this supposed to work if the cat just spends forever licking it off? Is the concentration of vinegar (half normal 5% acetic acid, half water) going to do damage to her insides?

Thanks for the help!

I think you should get the prescription from the vet. Nothing else works. It's a losing battle to use anything less.

@caspian915

Please stop using the vinegar immediately.  While it may be ok to use on dogs, my research suggests it is NOT ok to use on cats and if he's licking it off then he is ingesting it.

The best method, especially in a  high flea area is a spot on liquid treatment on the back of her neck like Advantage or Revolution available from a vet.  It lasts for 30 days.  Under no circumstance should you use a spot on treatment that you buy in a pet store, some of these are very dangerous.

The safest "natural" way to rid her of fleas is to dilute simple liquid dishsoap (Joy as an example) into sudsy water, bathe her with this which will stun (not kill) the fleas, and then comb her carefully with a flea comb, then rinse her.

But, if she is getting fleas as in indoor cat then it sounds like the problem is so severe that you would be bathing her constantly, so really, a spot on treatment is really the way to go in the long run.  A 4-6 month supply can cost between $35-$45.  Another reputable source is here.  http://www.drsfostersmith.com/product/prod_display.cfm?pcatid=23035