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Monday, April 4, 2011

It's NOT The Flea Product...Really!

As we're warming up here in the US we're starting to see "flea season emerge".  So this brings up a good time to talk about flea prevention again. I thought to bring this up after a reader in Chile commented on an older post about Frontline, believing resitance to be taking place in his area.  But before addressing that, I want to remind everyone of previous discussions on flea control.  Go back and read these if you haven't before, as I don't plan on repeating the same information.
Bugged By Fleas?
Winter Prevention?
That Flea Medicine Isn't Working!
eBay Flea Prevention
Follow-up On Fleas & Frontline
Yes, You Really Are Doing It Wrong
Even Yet More Flea Problems
Best Heartworm/Flea Preventatives?

Here's the bottom line...Advantage/Advantix, Vectra/FirstShield, Frontline, and Comfortis are all very effective.  Study after study has shown this.  Bayer looks at resistance to their Advantage products every year with samples of fleas from around the world and has never documented any resistance to their products.  Dr. Mike Dryden, a world-renowned parasitology specialist, investigated cases on suspected Frontline resistance at homes in Florida where "it wasn't working", and in 100% of those cases found that the product worked great but the client had unrealistic expectations or there was some other problem in flea control in the household; in NONE of the 30+ cases did he find any resitance or failure of Frontline.

So seriously, folks.  There is no documented resitance of fleas to these products that I've listed.  There is resistance noted to many over-the-counter flea preventions, so it can happen.  And the fact that there is no resistance now doesn't mean that there won't be in the future.  In 99+% of these products appearing to "fail" there is another problem besides the product itself:  overbathing, failure to treat all pets in the household, failure to treat the house and yard, large numbers of wild animals and/or strays carrying fleas into the environment, inconsistent use, expecting complete control in 1-2 months, etc.  The more I've looked into this over the years, the more I've heard the specialists discuss, and the more articles that I read the more I am convinced that any problems are NOT in the flea products (again, at least the ones I've listed and am familiar with).

Okay, I think I've just about exhausted the possible discussions on flea prevention.  Obviously, this is a very bothersome and frustrating issue to people, but there's also only so much to say.  Since I've talked about it numerous times over the last 2 1/2 years I probably won't say anything else unless new information comes out.  Hope there is enough information here for everyone!


  1. This is such an asinine post. Everything grows resistant to everything. It's happening with all of our ABX too. Yes, fleas are ABSOLUTELY growing resistant to these insecticides. Frontline doesn't work at all for me anymore. Advantage does, but only for a short time. This is annoying, but it was also inevitable. Why deny it?

  2. Just because things have the POTENTIAL to become resistant doesn't mean that they will. Parasitologists do look at resistance, and 99% of the time a lack of efficacy has nothing to do with the product itself. This has been proven again and again, as I have extensively outlined. Penicillin has been around for nearly 90 years and there are still plenty of bacteria that are just as susceptible to it now as they were back then. So saying that resistance is happening to ALL antibiotics is a fallacy. I'm not saying that resistance is impossible, just that with regard to fleas it is very rare or even not happening and that every time this is looked at it is overwhelmingly a problem with application or expectations of the product, not the susceptibility of the fleas to the product itself.

  3. " failure to treat the house and yard"....

    You are right! I never treat the house and the yard! So where do I put Frontline or Advantage to treat the house and the yard?

    I have had pets for more than 40 years and this year is the first one since I started using Frontline or Advantage where the fleas have gotten so bad. If I have to use an additional product o treat my house and yard now, after all these years, then something is out of kilter. Trusting the company that makes the product to inform us if it stops working sounds like a plan! The tobacco companies certainly let us know that cigarettes did not cause cancer. There is a long history of big companies who have told us the truth....or not told us the truth but hired people who would tell us what the company wanted us to hear.

    So.......who signs your paycheck?

  4. Reviewermom, my data and opinions come from more than just the manufacturers, but include studies and lectures from world-renowned parasitology specialists. I also don't appreciate the implication that my views are bought by any company, and such an implication is a direct insult to my intelligence. I actually don't carry or sell Frontline or Advantage in my practice, so I derive no money from my opinion of them. Before automatically blaming a given product, why not look at other possibilities? Are you bathing your pets more? Have there been changes in the climate where you live? Changes in the environment? An increase in wild or stray animals? The point of my blogs on this topic is that when a product seems to not work, people automatically assume that there is resistance or a poor product. Most people (and it seems like you are one of these) don't seem to consider all of the other possibilities and don't seem to realize just how complex of an issue this really is.

  5. Sorry, but I'm a biologist who uses these products, and there is such a thing as resistance. Frontline was completely useless in Huntington, WV, but Advantage worked great. Here in Hickory, PA we seem to have some resistance to Advantage, so will be trying something else. Just because there is resistance in one city or neighborhood does not mean they are resistant in the entire state, it would be impossible to screen for resistance in each individual population, so no one can actually say it doesn't exist. In fact, that would be the opposite of the scientific method. All that can be said is that it has not been documented in a laboratory setting. A new introduction of fleas from some other source could account for a temporary influx, but not an established population for 2 months on end, and fleas and flea dirt being consistently found on treated animals. You may feel insulted, but you are also insulting anyone who disagrees with you, assuming that they don't know what they're talking about.

  6. Great blog article, with some rather ignorant comments above. I'm a university academic and biologist (in the UK) who owns a cat. I suspected that the fleas on my cat were resistant to fipronil until I started digging down. This article is worth a read which deals with the puzzling observations that fipronil resistance certainly hasn't developed in field collected fleas. It certainly isn't unreasonable to guess that fleas might get resistance, but all of the published data supports the opposite view. Please check out Episode 32 of my podcast TheScienceShed when it comes out on Sunday 24 sept - we'll discuss it


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