Dawn on Dogs to Kill Fleas?

If you get the blue dawn dish soap it works very well ! I wash my dog with it and it helps a lot with killing fleas, if not killing them it makes them very slow and lazy so you can grab them. You should really give it a try.

I have done it with my three dogs, works great on the ones on them at the time but has no residual kill..  If you really want them all dead for a low cost try this http://www.amazon.com/Monterey-Spinosad-Organic-Garden-Insect/dp/B000BWY3OQ/ref=sr_1_3?ie=UTF8&qid=1343880063&sr=8-3&keywords=spinosad.  Spinosad is the active ingredient in Comfortis once a month tablet, and is in a glycol suspension.  I put a capfull on a piece of bread and feed it to my 50 lb+ dogs..  They will start scratching like crazy in 30min to 1 hours as the fleas start to die..   I also mix about 1 ounce up in a 32 oz sprayer and spray bedding, carpet and the dogs topically.

Kills the fleas on the dogs when they bite, new eggs will hatch babies will bite and they will die, after a couple of cycles you will be pretty much flea free.

Off label but have been using it for the last four years and the lack of fleas is great.

It also has been working great for spraying around the chicken run and house for flys, works good in the garden also. 

PM me if you have any  additional questions.
 

Bad news, if you're seeing fleas on the dogs and cats you've already got a flea infested house!  Good thinking to treat the environment immediately.  Check the product(s) you use to see which life stages they kill.  There isn't really a single product out there that will kill all life stages, so if all you are killing is the adult fleas (or the larval fleas) then there's a good chance you could be seeing fleas again in another 3 weeks.  Think of flea infestation as a pyramid.  Adult fleas that you can see are only the top 2% of the pyramid, the other 98% of the fleas hiding in your environment are in the form of larvae, pupae, and eggs that are waiting to hatch and grow into adult fleas that can bite your pets.  If you can get a product that will kill the eggs that would be best, otherwise you'll be seeing fleas again in another 3 weeks when the eggs that are in the environment start hatching out.  Regardless of what you use, it may be prudent to mark your calendar and do another thorough cleaning each week for the next 3-4 weeks.

Dawn will work to kill any fleas actually ON the animal.  ANY kind of soap actually will do this.  However, the problem is that it will do nothing for the fleas in the environment.  So as soon as the dog gets out of the tub the fleas will likely be right back on her.  The soap will also work to remove any topical flea control product you are using (which is a minor point since it clearly isn't doing a great job anyway and at 3 weeks out you'd be about due for the next dose anyhow).  The other problem (which is a bit more of an issue for you, being about due for another round of treatment) is that stripping the oils using dawn or another kind of soap will make any topical flea treatment you use in the days to a week following the bath less effective as it will interfere with absorption.

I would find another flea control product.  Vectra is largely permethrin based (36% of the active ingredients).  Unfortunately, permethrins have been around long enough that there are a lot of fleas out there that are resistant to them.  Whatever you switch to, I would consider applying it every 3 weeks instead of once a month, at least for the first 3 or 4 months to be sure you are getting any newly hatched fleas that your environmental clean up may have missed.  The flea life cycle, from egg to adult, is at it's shortest 3 weeks long (although the pupa stage can last for as long as a year if environmental conditions such as temperature and humidity are not favorable!) so reapplying every 3 weeks should get any newly emerging fleas.  Which brings me to the point that you may not be seeing a total failure of the vectra to work.  You could potentially just be seeing the newest fleas that haven't had a chance to be killed yet on your pets (although even I think that's being a bit optimistic).  Another possibility is that you could be bringing fleas in on your clothes from outside.  Most commonly, fleas hitch a ride in on the pets that go outside.  But in bad flea years (and this has been one thanks to the mild winters most of the country has had) you can bring fleas in on you.