Are You Poisoning Your Pet to Kill Fleas?

Hello Summer! Goodbye Fleas!

Ah, Summer. At least, up here in the Northern Hemisphere, that’s what’s upon us. More time outdoors, more exposure to sunshine and its feel good vitamin D, more exercise like swimming, body boarding, hiking, biking…

And, unfortunately, Summer means more insects. Most of whom have been on the planet longer than we have and won’t be leaving on their own accord anytime soon. Fleas are one of the most bothersome of the bunch, especially if you have pets.

Here’s a recent email I received that may speak to a feeling you share:

I am reluctant to try a safer alternative to Advantage for fleas
as I has a major problem with them over 2 years ago using dimotaceous earth,  essential oils such as peppermint, lavender and lemon as well as Flea Treats.  I live in a large dog friendly complex so it’s not like I can spray the area. The complex sprays every Wednesday and we live in such an out of control environment the fleas have become resistant to pesticides.

Comparing Methods

As a quick comparison of the basic options you face, here’s a chart:

Flea control table

Note: IGR = insect growth regulator.

I’ve never felt poisons were a wise choice for your animals. In poisoning the pests, there’s always a price to pay that’s carried by your animals, your family, and you.

Advantage has toned down their label a bit in recent years, but in the past, it was always a “teaching moment” for my clients and students who had never read the fine print:

  • Don’t drink while using Advantage
  • Don’t smoke either
  • Don’t get this on your skin
  • Don’t get it on your clothing
  • Wash both of the above like crazy if you screw up

…but you should feel entirely confident in squeezing this poison, that kills fleas, on your dog or cat’s shoulders.


More Tasty Oral Poisons

Years ago, when I first wrote my popular Non-Toxic Flea (and Tick!) Control page,

there was an oral drug (lufenuron) that was using your pet’s blood to deliver a chemical to the blood sucking flea. I couldn’t recommend that to the most desperate clients, just because, well, it was delivered by your dog or cat’s blood!

What’s wrong with that picture?

Since then, we’ve unfortunately seen several others come to market:

  • Comfortis (spinosad, a bacterial toxin, with an all too common side effect of vomiting)
  • Capstar (nitenpyram, a neonicotinoid insecticide, whose class likely is responsible for our bee population decline)
    Starts killing fleas as fast as 30 minutes after ingestion!
  • Nexgard (afoxolaner), and
  • Bravecto (fluralaner, both from Merck/Merial)
    both killing the blood suckers via your pet’s blood, the latter within 2 hours and lasting for 12 weeks (!)

I wish I was making all this up.

Search Facebook and you’ll find pages dedicated to tracking illness and deaths associated with these last two.

Best Prevention, Big Picture

You’ve heard of natural resistance, especially if you have read (or listened to) my book, Vital Animals Don’t Get Heartworms!. It’s ultimately your safest and best bet in preventing fleas and ticks from wreaking havoc on your pets. And spoiling your Summer.

To learn more, click this button:

It turns out that my heartworm prevention without drugs book up there will also, when its principles are well applied, create natural pest resistance.

I told you about my friend Dana Scott’s experience earlier. Her dogs loaded in a van with a pack of conventionally poisoned and multiply vaccinated, kibble-fed dogs who had a big flea exposure on a show trip. Hours together in that van to get back home, and upon arrival, guess which dogs were crawling with fleas?

Yep, the conventionally raised guys. None of Dana’s pack. In fact, not a single flea!

So, the best prevention ultimately is always this: raising wildly healthy, naturally disease resistant, remarkably shiny Vital Animals.

That’s what this site is here to help you do, in fact!

Dig in and take your animals up a notch. Or several notches. A great place to start is a link in the top of every page, appropriately titled Start Here.

Tell us in the comments if you have any fave ways of preventing fleas and ticks without poisoning the pets, the people, or the planet.

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  1. Vicki Smith on January 30, 2018 at 8:01 am

    Watched episode 5 “truth about vaccinations”. Excellent. It made me reconsider some of my vets practices for my cat. I have switched foods and am using Sojos and what he eats outside. He typically ends up with worms at some point. I have treated this with Cina but is there more I could do nutritionally?

    • Will Falconer, DVM on January 30, 2018 at 9:31 am

      Hey Vicki,
      A full on, raw balanced diet would be a help, but if these are tapeworms (rice grain sized), it usually takes a professional’s help to get her constitutionally prescribed for with homeopathy.

  2. Merrick on January 23, 2017 at 10:37 am

    Hi, Dr. Falconer — terrific website and content!
    My last dog, a Lab/Chow who passed last year at 15yo, never took Comfortis, Trifexis, Nexgard or Bravecto because, as a member of the Facebook group “Does Nexgard Kills Dogs?” I learned a few things ahead of time. Frontline and Advantage no longer worked in my area, so I resorted to natural methods. Unfortunately, I was never really able to control the fleas appropriately on her for the last six months or so of her life.
    With my new dog, a Wirehaired Pointing Griffon mix, I started out very leery of everything. When he first came into the shelter who got him, they gave him Comfortis with, supposedly, no ill effect. He was then taken in by a rescue, who gave him Advantix with, supposedly, no ill effect. When I adopted him I knew Frontline wouldn’t work, and I didn’t want to use Advantix (don’t like combination drugs!), so I just went with Advantage, which I never used on my last dog. It “seemed” to work for awhile, but then, no. And, to top it off, I have been continually dealing with a flea infestation in my home (currently trying to fight off with dehumidifier, diatomaceous earth and, although haven’t used yet, FleaBusters).
    When I went to a dermatological vet for intense itching (flea bite, pollen, or both — although I tend to think more pollen given the itching went away, although the fleas necessarily didn’t), he didn’t want to prescribe Apoquel (good!) but instead the more “old-fashioned” Medrol. My dog was on that for two weeks, definitely helped. Daily pills first week, every other day the second week til done.
    During that initial appointment we talked about flea meds and I told him I didn’t want to use Nexgard, Bravecto or Comfortis — and he said, why don’t you use Capstar? He told me that it’s actually the safest, goes in the system and out within 24-48 hours. Give him one every other day. He said most people don’t go that route because it gets very expensive, but it’s the safest.
    So, I started Medrol and Capstar the same day.
    It was either during the end of Medrol or several days later, I noticed that my dog had developed a sort of….reticence, best word I can think of. Where before he would happily run out the door to the front gate for me to take him on a walk or to the dog park, all of a sudden he wasn’t so willing and I actually had to start pulling him out. Or he’d come outside on the patio but just stand there looking at me and even though I call him over “Let’s go, Perry!” I have to go get him. Also, in the car, he had done fine for months — but since the Medrol and Capstar he seems to have high reticence and even, at times, fear, while in the car. Just today, although I usually put him in the back, I had to put him in the front seat. In the past, no problem. Now, he seems very unhappy, head bowed.
    Here’s the thing, though, he’s is actually perfectly normal, as before, when we’re on walks, at the dog park (very energetic and happy), visiting my landlords upstairs (who care for him while I’m at work) and generally while we’re at home, he’s FINE. It’s just these two types of situations — getting out of the house, and in the car — but, still, very troubling to me since it seems to be continuing. It’s almost as if “I’ve ruined a perfectly happy dog.”
    After a couple of weeks and my thought that this “personality change” might die down, and we were off the Medrol, I was thinking about Capstar and read more about it and, although found nothing conclusive, I decided it best to take him off of that completely. By then he had probably gotten approximately two dozen doses over the course of a month or so.
    That’s the backstory. So, any thoughts about this as far as (a) Medrol and long-term effects even after you stop using it, and (b) Capstar and the fact it’s related to nicotine and that, sure, it leaves the body after 24-48 hours BUT, with repeated use, can actually damage the system?
    Apologies, already gone on too long here but need to add one final note: I decided to take him to a holistic vet, who I thought was very good in many ways — except, hm, for flea control, she said “the natural methods just don’t work” (or she may have said they don’t work “here”? — I’m in a beach city in Northern California) and she did say she absolutely doesn’t like Nexgard/Bravecto, combination drugs like Trifexis, BUT that she can recommend, and sell, one and only one: Comfortis. She said she doesn’t like giving any flea poison to any dog but that in the heaviest season you need something and that is the one that has the least danger / side effects BUT using it only a few times a year when fleas are at their worst and then in off months (e.g., winter) simply frequent bathing and some natural methods would be sufficient.
    Thoughts on that one? She convinced me to the point that I actually bought a box, but haven’t used it yet.
    Thanks so much for your time.

    • Will Falconer, DVM on January 24, 2017 at 2:04 am

      Hi Merrick,
      First, I’d be quite concerned with Medrol for anything but emergency, very short term use. It’s a corticosteroid, and they are supremely good at suppressing symptoms. The end result of suppression is often worse disease than what you suppressed.
      And, I’m a broad brush stroke person, so poisons in general, but especially if you’re warned about human exposure (Advantage) are never even on my short list for pets, Comfortis included.
      Flea Busters guarantee no fleas for a year! Hard to beat that, and it’s a borate compound, so quite safe, even if accidentally ingested.

  3. Bonnie on June 19, 2016 at 9:58 am

    So what about cats and fleas. And if the cats go our and come back with them and even worse….ringworm ?

  4. Susan on June 16, 2016 at 9:27 pm

    Peter- try giving your dog colostrum. You can find it at the health food store. It will balance the bacteria in the gut and take care of the digestive problem. Works for my dog (and humans) every time. Pour contents of 2 capsules in warm water, mix and offer 20 min before meals. Do this for a few days. Best of luck!

  5. Mina on June 16, 2016 at 12:37 am

    If you all want to know how these anti parasite drugs are being passed for market, go to this Facebook page. Stop Experiments at Young veterinary research services! These poisons are being injected into innocent lost and stolen pets who live in confinement their entire lives in little cages. They get no sun no play no enrichment activities. Imagine being a cat and living your whole life in a cage, only being handled when used to be experimented on restrained and drugged with needles repeatedly. Imagine you’re a dog and you live your whole life inside a small kennel. These drugs are being passed on sick, and depressed, unhealthy and abused dogs and cats.

    • Sherry on June 16, 2016 at 8:58 am

      Thank you Mina for this information I posted it on my facebook page and ask everyone to keep sharing it. This just totally breaks my heart.

  6. Mina on June 16, 2016 at 12:28 am

    I have also put up
    A cat fence to keep my yard free of neighborhood animals. I’ve done so much and only have fkea issues in summer, thinking now of moving to Nevada or Montana. I should t have to poison my animals just so they can go outside. I want a pesticide free life I don’t use poison I use all natural sprays for my house and yard. I am pissed off that I used advantage which probably won’t last anyway. The pharma industry is trying to phase out topical poisons. They want us to buy the pills oral PEsticides so they are purposefully making it less potent so that tou think the fleas are immune to it and you buy the pills from your vet. Try HS11 and artemisia combination and black walnut! Colostrum and a whole body immune booster. I’m not sure what your book says but why don’t you just share your knowledge with us? Are you just trying to make money selling book. If you really care there would be no book and you would have a free manual.

  7. Mina on June 16, 2016 at 12:19 am

    I was using only wondercide every day I took them out but in the summer it doesn’t work for my two small dogs with thick coat it still works on my senior golden retriever. I feel horrible I had to get advantage and they were so depressed when I applied it they just curled up in their beds and had no energy. It was awful. I am
    Going to
    Try to
    Supplement them
    With HS11, artemisia combination and black walnut. My golden eats his food w supplement but I can’t get the little dogs to. They eat raw on some days and honest kitchen on others and home cooked. Maybe the herbs create an un favorable environment for fleas. I get his blood tested and he never has heartworm.

  8. peter on June 14, 2016 at 8:25 pm

    Hi Dr Falconer,
    I didn’t know where to post this but my dog has been having diarrhea for almost 2 weeks now. I have been feeding her raw for almost a year with no issues, she appeared to be very healthy, finally. We went on a backpacking trip recently overnight (8 hour hike first day, 5 hour hike second day) and it was strenuous, my dog is fit but we normally just do 30 minute to 1 hour hikes, she wasn’t conditioned for this trip, but she did very well and was off leash, too. i have excellent voice control but i could not stop her from drinking out of brooks, streams and occasional stagnant water. i also changed her food cold-turkeyfrom raw (Prey model) to commercial raw Stella & Chewy’s. She has a history of GI issues so this prob wasn’t smart but she has been on it before and liked it. Anyway she ate that and I also let her drink bottled Smart Water that i had. When we’re home she gets filtered water. When I got home I also stupidly put her right back on her regular raw with no slow transition or rest. So lots of factors why she has diarrhea. But her desire to go was frequent and urgent, and it was bloody and watery. No fever though. I had vet run fecal float, a giardia antigen, a leptospirosis PCR and it all came back negative. I understand it can be hard to diagnose but man this has got me stumped…. She was put on 2 rounds of metronidazole and 3 days of panacur. And a probiotic with a bland diet of boiled grass-fed beef with a hard boiled pasture raised egg. And now we’re adding apple cider vinegar. Her pool have barely improved. Hardly formed and very loose. And straining/constipated. Vet doesnt know what else to do. I am also giving her some chicken bone broth. Any advice for me?
    – Peter

    • Will Falconer, DVM on June 15, 2016 at 3:14 pm

      Yes, Peter: get thee to a veterinary homeopath! It’ll be cured rather quickly when the proper remedy is arrived at. This isn’t chronic disease, it’s acute.
      All the best.

  9. Rachel on June 14, 2016 at 3:45 pm

    Great timing of this article, Dr. F! I use Borax for flea outbreaks. (You can find borax in the laundry isle of the grocery store or places like Walmart or Target.) Borax works like diatomaceous earth. I sprinkle borax (20 Mule brand) on the carpets/rugs where my dog sleeps/hangs out, even the sofa- because that’s where he likes to sleep while we’re not home. And I do the same to his doggie bed. (Be mindful not to inhale the powder or apply it with your pets around.) I let it sit for a while (about 30 minutes or so) then vacuum it up and dispose of the vacuum contents immediately. If the situation is really bad, I also bathe my dog with borax. It leaves a bit of a residue on him but it’s a much better trade-off than the fleas.
    My dog is also exclusively raw fed, no vaccinations/no flea meds or heartworm preventatives. And I use homeopathic remedies for any ailments that do come up, which isn’t often.
    I had a flea outbreak almost two years ago and I haven’t had another since. I’m not sure if it will remain this way but we’re both happy to be flea-free right now 🙂

  10. Bonnie on June 14, 2016 at 8:30 am

    What about cats ?

  11. Susan on June 14, 2016 at 4:06 am

    I am far more afraid of what these poisons can do to my dog than I am of occasional fleas. My dog is raw fed and only vax he gets is the rabies one every 3 years- and the only time the fleas were out of control for a bit was after his last rabies vax- more than just a coincidence, I think? Even every 3 years is too often for that. Diatomaceous earth helped a lot. So did Wondercide (makes me sneeze too much) and an herbal powder I got (because of the sensitivity to the cedar) A plain old bath will help.

    • Will Falconer, DVM on June 14, 2016 at 6:11 am

      Nice catch, Susan! Rabies vaccination –> fleas out of control. I agree, far more than a mere coincidence.
      Immune confusion, systems down, chemistry changes post vaccination, likely is like the bat signal: “Yo, parasites, we’ve got a nice home for you!”

  12. Sun~Rose on June 14, 2016 at 2:08 am

    Like most of what You say, and — as I think You’re pushing the raw meat diet — how animal lovers can be so blind to other animals suffering. Surely God did not create any of us to consume each other. Check out Genesis 1.

    • Sun~Rose on June 14, 2016 at 2:11 am

      Here’s the passage:
      29 And God said, Behold, I have given you every herb bearing seed, which is upon the face of all the earth, and every tree, in the which is the fruit of a tree yielding seed; to you it shall be for meat.
      30 And to every beast of the earth, and to every fowl of the air, and to every thing that creepeth upon the earth, wherein there is life, I have given every green herb for meat: and it was so.
      31 And God saw every thing that he had made, and, behold, it was very good.

      • Will Falconer, DVM on June 14, 2016 at 6:13 am

        Hmm. So, where do the wolves and lions fit in that view?

      • Dede on June 14, 2016 at 4:25 pm

        Sun-Rose: That was before sin entered the picture. After that happened, God provided animal skins for a covering and made clothes for the naked Adam and Eve. An animal died for those skins. After the flood, God gave Noah new instructions for diet and authorized man to eat meat. The sacrificial death of the innocent animal points to Christ dying for mankind as the covering for our sin.

  13. Jacqueline Cutler on June 13, 2016 at 11:18 pm

    I have 2 dogs, a Sheltie and an American Shepherd. They are both on raw diets with organic vegetables, and the addition of sardines a couple times a week for the Omega-3. They also get probiotics every day in the form of Kefir, and a few organic raw eggs every week. Their coats are beautiful and shiny, their teeth look very good and they have lots of energy. My Sheltie never gets fleas, but my American Shepherd gets them every year. I have bamboo floors, I vacuum my throw rugs (or wash them) 3 or 4 times a week, I use Vet’s Best Yard Spray and indoor spray, I have used nematodes, diatomaceous earth, organic shampoos, etc. But he still gets some fleas every summer. It is hard to see him scratchcing and biting his back. I use a flea comb and brush him every other day. I bathe him and do a vinegar rinse. None of this seems to keep him from getting fleas. So where do I go from here?

    • Will Falconer, DVM on June 14, 2016 at 6:07 am

      In preparing this post, I came across someone saying something to the order of “cleaning your house like a crazy person won’t prevent fleas.” And I totally buy that, and hear stories like yours fairly regularly.
      It’s not a cleanliness issue. It’s a flea reproduction issue. If my clients are using the Non-toxic Flea Control principles and still seeing fleas, it means somewhere in the home, flea eggs are developing into adults. When an IGR is used on every surface flea eggs could fall on (they roll off the coat of your dog), they shouldn’t develop to adults. Period.
      So, think where your dog lies or hangs out. Is that surface treated to prevent flea eggs from hatching or larvae from moulting? If not, get the IGR on there. And don’t wash it away! Or if you have to wash, then reapply it. It lasts 7 months with one application.
      The other thing, especially when there is more than one dog in the family but one is always the “flea magnet,” it’s time to seek a veterinary homeopath. There’s chronic disease lurking in that individual that diet and poison avoidance hasn’t been enough to cure. Probably vaccinations in the background.
      Check my Resources page for the AVH list, and hire someone who does mostly or only homeopathy. Where they are located matters not. Work by telephone if you don’t have a vet homeopath in your area. Odds are you won’t, sadly.

      • Sherry on June 14, 2016 at 10:16 am

        In your above comment you mention IGR what is that please?

        • Dede on June 14, 2016 at 3:55 pm

          IGR is insect growth regulator. We had a horrible flea problem last year and so did our 2 neighbors. We found out a new neighbor had moved in down the street from us and they had several outdoor cats. These cats came in our yards and brought the fleas. We all used Martin’s IGR and nothing else. It solved the problem for all of us and our dogs. We purchased it from for less than $20 each. Like Dr. F said, it lasts for 7 months when used indoors but must be reapplied more often outdoors because the sun breaks it down. We each sprayed our yard twice and our homes only once.

      • Sandra on June 17, 2016 at 4:20 pm

        What does igr stand for

  14. Donald Mitchell on June 13, 2016 at 11:09 pm

    Fleas a big problem why don’t you talk about flea prevention more or state that the book deals with fleas as well as heartworms more loudly.I saw were u said it as I had to read a lot to find that statement. BUT I GUESS IM ASKING WILL THIS HEART WORM BOOK HELP WITH FLEAS AN IS THE GUARANTEE FOR FLEA ALSO.

    • Will Falconer, DVM on June 14, 2016 at 5:54 am

      Hi Donald,
      If you follow all the steps outlined in Vital Animals Don’t Get Heartworms, your dog won’t get fleas, either.
      But I can’t reasonably guarantee you’ll be either HW-free or flea-free, now can I? Impossible for me to see if you’ve done everything in the protocol properly.
      Just know this: if you take this information and run with it (apply it steadily in your animal’s life), you’ll be amazed at the outcome. And wonder why you ever felt you needed to buy poisons to give your dog. It’s that transformative.

    • Kelly Hall on June 14, 2016 at 8:14 am

      Donald, when I got my little Chico two years ago my whole mindset had changed about how to raise a dog. Previously my dogs stayed in the backyard, got HW meds, flea meds and ate kibble. Yes, I am ashamed to say I was VERY ignorant of dog health and the implications of our trusted pharmaceutical establishment. Since my own health has become a priority, it was natural that my dog’s would too. Since Chico, I have added two more adopted dogs and rescued two from the street. They all eat the same (raw), get no HW meds, no paraciticides and no vaccines. We go on long walks every day. That is my protocol for all jumping, flying pests. As assurance I add brewer’s yeast, garlic, and diatomaceous earth in their food. I use Wondercide and Halo spray to kill and protect from the outside. I vacuum ALOT. All this I learned on my own. The internet is a wonderful teaching tool with a strong and supportive community. It was all verified by Dr. Falconer and he ultimately gave me the courage to dump the HW meds. So do your homework. It’s not that hard. The one thing that is hard is deciding if you have the conviction to do the work. I do because my dogs are all worth it!

      • Sherry on June 14, 2016 at 9:55 am

        Kelly, you say you add brewer’s yeast, garlic, and diatomaceous earth in their food how much do you add of each mine range from 8 lbs to 17 lbs and I use wondercide and I feed raw which is Primal and let me tell you my dogs are still getting fleas I spray them down twice a day with the wondercide lemongrass & cider and we go for a walk and when we get home they have fleas I am totally at my wits end they haven’t been vaccinated in years and they have fleas I just don’t know what to do anymore I am so stressed out and I vaccum every day wash they bedding everyday and they still get fleas and advise would be most welcome by you or doctor Falconer.

        • Kelly Hall on June 14, 2016 at 12:11 pm

          Sherry, I’m in Houston so fleas are like mosquitos. A way of life. Some years are better than others. This year seems to be “one of those years”. Last month I spread nematodes in the front yard to see if I could get a head start on the flea cycle. I am positive that I get a few hitchhikers as my dogs all scratch a little. This is of no concern to me. I scratch a little when my skin gets dry so it may be fleas or it may be dry skin. I have only seen one flea on one dog. I make runny eggs for them in the morning, add in some brown rice and minced veggies. To this I add about 1 tsp (slight heap) brewers yeast, dry garlic (1/2 tsp) and fresh ground cloves (pinch) as I have heard this will kill HW microfiliae. At night I toss about 1 tsp in my big guys bowl and 1/2 tsp in my smaller dogs bowl of diatomaceous earth. I also add a splash of Braggs ACV to keep their ph level as my vet said brewer’s yeast can affect that. Not sure if true but the ACV is good for them anyway. I spray morning and night with Wondercide and use Halo spray also. I agree with Dr. F as your one guy may have underlying issues. One of mine, little Tink has terrible allergies even though on this protocol. She will be Dr. F’s next patient. (:

          • Sherry on June 16, 2016 at 8:35 am

            Kelly thank you for your reply but how in the world do you get your guys to take the ACF mine would spell it and not touch their food and suggestions. Also they aren’t getting a lot of fleas just like you said its more like hitchhikers and its only been this year and we have lived in these apartment’s for several years and never have had a problem
            Also is Dr. Falconer taking new clients I live in Irving, TX and I would drive to Austin if he is please let me know because the last I heard he wasn’t and that was about a year ago.
            Sherry Richardson

        • Marty on June 18, 2016 at 10:36 pm

          Sources of raw protein diets should be organic- GMO free- & grass grazed-
          Fleas-parasites will be still attractive to dogs being fed second hand grain-
          Grain produces the parasite attraction- smells to parasites akin to Fritoes!

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