Diatomaceaous earth takes a little while to work, but it does work. It's a very fine powder, so you have to be careful to avoid either the dogs or yourself inhaling it. It also must be food grade, not the kind used in pools. I don't personally think any of the natural remedies work well when fleas are already present and I'm always cautious about recommending EO usage for animals, particularly if there are cats in the home. Nexguard is supposedly safe for puppies 8wks and over 4lbs. I can't say how it works because I haven't tried it myself, but my daughter received samples from the rep at her clinic and the person I gave the box to said it worked well.
When I brought Ella home at 5 weeks-ish, she was infested with fleas. I don't use any flea products on my dogs because I've never had a problem and I was very unhappy at the thought of bringing them into my home. I went to the store and bought Dawn dish soap, a flea comb, and Capstar. Dawn is safe to use on puppies. Get her in the tub, lather her up and let her sit for a while. The Dawn will kill the fleas and you can comb them off. Dawn works better than any flea shampoo I've every used. Capstar starts working to kill the adult fleas on the dog in half an hour, but it's only for a short amount of time. It doesn't work like Frontline, but you can give more than one a month if you have to. Comb off those dead fleas. Change bedding frequently and vacuum, emptying out the dust catcher outside every time. Use the flea comb daily. Even if you choose to use something like Nexguard, I would still do the above right now to avoid any cycle starting.
