diatomaceous earth

Hi...I came here having gone crazy with an indoor short hair black and white female cat 3years old infested suddenly with fleas. I have one cat that goes outdoors with me only (never runs away etc only sits by me on the lawn etc) a Mainkoon boy.
Last year beginning of spring I gave them an anti flea bath they HATED it (it was a first) so this year I opted for a spray and god do I regret it. ZODIAC monstrosity send my short hair cat into a frenzy of drooling and vomiting for two days till I rushed to the vet
197$ later (the last thing I need) she got an injection against the nausea and one against fleas that was Friday 3pm. At home gave her a wash with gently soapy dish washing water mixed with half a dose of the flea bath..
This morning back to the shop to return the spray they refused to take back (what do I expect) but they offered the diatomaceous earth. Where did that come from NEVER EVER HEARD OF IT and had cats nearly all my life battling on and with
flea come and go and collars and baths etc. So today Monday after vacuuming the entire house and spraying one last time against fleas I sprinkled diatomaceous earth into all carpets bottom and top that are lying on the hardwood laminate.
Then into her fur but must say (I thought this will work within hours) but at 6pm she still had at least 30 fleas on her at the last combing.
Not here to complain just asking WHO LONG will it take for the diatomaceous earth to work and kill the fleas. I did reapply a bit again on her bum and behind her ears and on her neck. The other cat not seem to phased at all with fleas ever.
Either they dont like him or he is a super cat ..what else to do. Washed ALL pillow covers and blankets and disinfected all window sills etc.
Many more things I will like in this forum we grow 120- sq feet of oraganic veggies here in Vancouver Canada. and DEATH to ZODIAC products never ever again. The anti flea spray is really leathal.
Thanks for any insights for other cat owners using the diatomaceous earth. Today nearly used a whole pot of 500gr $16.99. Naturally hope I dont need that every week at that price.
The brand is Wholistic pet organics sorry some of my keyboard doesnèt work today.

Vic Staple : Welcome to Permies, glad to have you as a new member, over 17,000 strong! you will always remember your 1st few posts! This is an easy one !

At the right hand top of this page between the Permies banner and the Permies video of the day, you will find the search button in the 'Permies toolbox' ! Click
on the search button and the go to the bottom of the page and select the google search engine type in Diatomaceous Earth ,and set your search for the Permies
Threads/Pages ! - You will get a lot of information on How diatomaceous earth works. Paul Wheaton has made himself an expert on this topic Good Luck !

For the Good of the Crafts ! Be safe, keep warm ! As always your comments and questions are welcome and solicited ! pyro - magically Big Al !

Expect it to take a few days. I've experimented on some bean beetles (hard cuticle, like fleas have) and it took 4 or 5 days for the last ones to succumb.

Also, cats lick their fur, so the cat is going to ingest DE and dead fleas. Not like that is going to cause a problem though -- the DE will take care of internal parasites as well. I would suggest applying a light dusting every other day or so, maybe rub it good into the fur (trying not to breathe any in) and be patient. The fleas have to come into contact with the DE, wallow around in it, get cut up by it, and then get dried out and dessicated. If the cat likes being brushed, you can make dusting part of a regular routine, and then you can do a count and see if it is working on the fleas.