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Fleas Aren’t Funny, but Neither Is Poison

The following post was originally published by Karen on KP’s Dog Blog, May 29, 2008.

About 15 years ago, I was prescribed an antibiotic that had the unfortunate side effect of making me extremely itchy all over my entire body. It was truly unbearable and lasted for a couple of days. I would definitely categorize that experience as “torture.”

So now, whenever I see an itchy dog, I take it very seriously. Canine itching can have numerous causes, but probably the most common one by far is fleas. Some dogs can be crawling with fleas and not even scratch, while others become completely overwhelmed with itchiness from a single flea because they’ve developed flea allergydermatitis.

When you’ve got a dog in a tortured state like that – or if you’ve suddenly become aware of a flea infestation in your home – then you might understandably become tempted to “do whatever it takes” to kill every last one of those fleas and fast, including bringing in the big guns: the whole arsenal of heavy-duty pesticides.

The thing to remember, though, is that almost all flea-control products, including the newer, topical ones, are bonafide poisons, designed to kill (that’s what the suffix “-cide,” as in “pesticide,” means). Even the inert ingredients, which often make up the bulk of the product, can have harmful effects. Pesticide companies are not even required to say what they are on the label (it’s a trade secret!).

Adverse reactions that have been reported for the various topical flea-control products include neurotoxicity, cancer, organ damage, and skin problems. It was less than two years ago, when I saw firsthand exactly how harmful this type of product could be. There was a knock at my door, and I opened it to find my former disabled neighbor sobbing hysterically.

She had hobbled over to my house to beg me to take her cat to the vet because the cat was having seizures and bleeding profusely. I rushed to her house to find the cat covered with blood,she had bitten her tongue. I bundled them both into the car and raced to the vet. During our car ride, with the cat seizing uncontrollably, my neighbor explained that she had put a Hartz Mountain topical flea product for cats on her two cats the night before.

Tragically, her cat died in the exam room right after we arrived at the vet. I tried to console her on the sad trek home and went inside with her to make sure she was going to be OK. And wouldn’t you know it, her other cat, Cotton, was now seizing too. Thankfully, her second cat had not bitten her tongue, but her seizures were quite violent. Off we went to the vet again. Cotton spent the next 24 hours in the emergency room, but she survived and was finally able to go home. That product has now been banned.

But how many people and their animal companions had to go through a similar tragedy before the ban was imposed? Last month, I received an e-mail message about another, brand-new flea control product, called ProMeris. The writer applied ProMeris to her seven dogs and this was the result:

Within less than 2 hours after applying, 4 of my dogs had vomited from 2-4 times, 3 were disoriented and stumbling, 1 was dragging his back leg, 1 was salivating. I had very similar symptoms like an allergic reaction. My lips were swollen, eyes very red, mucous membranes such as eyes, nose, and mouth were stinging. I was very disoriented, dizzy equilibrium and not able to drive. To make this a short story, all 7 of my dogs were admitted to the hospital for veterinarian care, and 3 of them remained for care, IV fluids and observation for 24 hours. I was in the emergency room. I’m home now and so are the dogs. We’re all feeling much better. Vet bills were over $2,500 and Fort Dodge is paying for these. Not only can the product cause this reaction, it has a highly noxious odor that permeated the house and is just starting to dissipate after 3 days.

Obviously, not every dog is going to experience such extreme side effects, but some will. The immune-compromised, the elderly, the young, and the sensitive are all at risk from exposure to chemicals.

But there are ways to lessen the exposure and the risk. If you must use a topical flea-control product because you have many dogs or you have dogs with an extreme sensitivity to fleas, use only a product prescribed by your vet. These tend to be the safest ones (but don’t consider them harmless, they’re not). Don’t use a product that kills every pest under the sun. If you don’t have a tick problem, then don’t use a product that also kills ticks, for example. Use the product as directed on the package, but use it only as needed.

So, for example, if a month has rolled around and it’s time to apply the product again but you don’t see any fleas, then wait. Depending on what part of the country you live in, you may only need to use it for half the year or less. If you have both healthy and unhealthy dogs, try just putting the product on the healthy dogs. It should still have the same effect while sparing your immune-compromised dog the chemical exposure.

And if you have just one or two healthy, non-allergic dogs, you can probably get away with using my tried-and-true pesticide-free program:

Comb your dogs every day with a fleacomb to remove any adult fleas. (You’ll have to kill the fleas?I deposit them into a jar and then put the jar into the freezer. I figure that’s how fleas would normally die.)

Vacuum frequently and put the vacuum bag in a plastic bag in the freezer or throw it out (apparently, fleas can escape from the vacuum bag back into your living area otherwise). Launder dog bedding often too.

For skin health, give your dogs a B-complex vitamin every day as well as flaxseed oil if your dog is not sensitive to it (some are).

Spray an insect growth regulator on your carpets and hardwood floors every six months. (This is obviously a chemical and, thus, not ideal, but I think it’s better than a pesticide, it’s not being applied directly to the dog, it’s only applied twice a year, and it really does prevent a full-blown infestation.)

Consider giving garlic or black walnut capsules to your dog as a flea repellent. These are controversial, and you should use the bare minimum, but they can be very effective. Do a little research so you can make an informed decision about whether to use them. I’ve used both for extended periods with no ill effects that I could detect.

Commenting is closed.
  • irma says:

    DaNgER don use Sentry Natural defense on cats the main ingredient is toxic to cats. If your kitty accidentally ingests something with peppermint, she’ll certainly be bothered. Cats may get upset stomachs, liver damage or experience central nervous system problems. Signs of the latter include drooling and loss of appetite. Even putting peppermint essential oil on your pet can be dangerous: one drop of essential oil made a cat so lethargic and unresponsive that her owner sought emergency veterinary attention, aromatherapist Kristen Leigh Bell warns. The ASPCA suggests you avoid using peppermint products in areas of the home your cat can access to avoid accidental ingestion or inhalation of peppermint. If you notice your cat appears lethargic or unresponsive and you find evidence that she ingested or inhaled mint, take your pet to the vet immediately.

  • Maggie says:

    In researching topical flea medications for cats, I found quickly that Frontline and Advantage are the safest, and others can frequently cause severe side effects. Thought it was worth mentioning. So if you absolutely need to use a flea med– say, your pet is allergic or just completely miserable– these are the ones to go with.

  • Pet Owner Against Hartz says:

    I know this is long, but please take the time to read it.

    • Since 2000, there have been more than 33,000 reports of death and serious injury to pets as a result of using Hartz flea and tick products.

    • Respectable veterinarians have long opposed Hartz’s use of phenothrin—an obsolete lawn pesticide known to cause hypersalivation, vomiting, ataxia, muscle tremors, hypo- or hyperthermia, seizures, paralysis, and major organ failure in both cats and dogs—as well as other toxic chemicals.

    • In 2005, under pressure from outraged pet owners whose animals were harmed or killed by Hartz flea and tick treatments, the EPA required Hartz to phase out phenothrin-containing flea and tick products for cats.

    • As of March 31, 2006, the sale and distribution of Hartz’s phenothrin-containing flea and tick products for cats has been terminated.

    • Despite the ingredient change in Hartz’s flea and tick treatments for cats, cat owners continue to report adverse effects, including pet death, in massive numbers.

    • EPA’s product cancellation order did not apply to Hartz flea and tick products for dogs, and Hartz continues to use phenothrin in a concentration of 85.7% in many of its dog flea and tick products.

    • Unsuspecting cat and dog owners looking for an inexpensive flea and tick treatment continue to unwittingly poison—and even kill—their pets.

    • Avoid ALL of the following:
    –Hartz (Hartz Advanced Care, UltraGuard Plus, UltraGuard Pro)
    –Sergeant’s Pet Products – (Sergeant’s Flea & Tick, Sentry Flea & Tick)
    –Farnam – (Adam’s Flea & Tick, Bio Spot, Scratchex Flea & Tick Products, Flys-Off)
    –Wellmark International (Zodiac, Vet Kem)

    •Ask your trusted vet to recommend a flea and tick treatment. Advantage and Frontline have a superior safety record. Also, there are non-chemical alternatives!

    Visit and for further information, and join the campaign against companies who are profiting from the sale of highly dangerous flea and tick products!

  • Christina says:

    You can also put 1 tsp. of organic white vinegar in your dog’s water to repel fleas!

  • Kristina says:

    I have been a vet tech for many years now and I have seen the damage fleas can do, especially in the South where we have them year round, and I just thought I would throw my two cents in and hopefully give some helpful advice. A really good trick to help get rid of fleas in the house without exposing your pet to harmful chemicals: go to a PET SUPPLY STORE (not Wal-Mart, not a tractor supply, ect) and get a decent flea powder (like a carpet powder), but instead of putting it all over your house, put it directly into the vacuum bag, then vacuum the floors (even hard floors), drapes, furniture, ect. Also, if you only have a few fleas, Dawn dish soap (the same thing used to bathe ducks caught in oil spills) actually works really well, just make sure you follow it with a skin/coat nurishing oatmeal based shampoo. And yes yes yes on the omega fatty acids! Fish and flaxseed oils are AMAZING…for EVERYONE!

    Hope it helps.

  • Lindell Vecchio says:

    Put about an inch of alcohol in a paper cup. Dip a Q-Tip into the alcohol. Hold pet in your lap or let lay on floor. Touch each flea with alcohol-soaked Q-Tip. Place flea in alcohol cup. Repeat until all fleas are off your pet. Flush fleas & alcohol down the toilet. Takes patience but works. Pet loves the attention and is grateful for the relief.

  • michele says:

    Hi there all you lovely peta
    I put a piece of amethyst quartz crystal in my cats
    water bowl , it works wonderfully has had no side affects and I have not needed to treat with the poisons for two years now.

    The crystal will out live us
    so it is very economical , I just give it a wash with a scrubby sponge each time I give fresh water to prevent scale and bacteria that might build up .

    It does not need to be an extra large piece , I use a deeper bowl and the weight of the stone keeps it on the bottom so there is no danger of my cats swollowing it.

    Once you have finished with the stone it can go back to nature in to the earth .

    Michele : )

  • Kristine Davies says:

    This comment is in response to the above MR RYAN NOONAN from PROMERIS.

    Did I hear you correctly?
    “The clinical signs reported are similar to those observed in dogs following deliberate oral exposure to ProMeris during safety studies conducted prior to the approval of ProMeris”.

    How dare you come in here talking about NASTY animal testing. Your statment is not going to sit well with people here. Times are changing Ryan it is time for companies to find alternatives to animal testing. I for one will not use a product that was used and tested diliberatly to harm an animal. You know your product contains pesticides and harmfull chemicals. Hey I have an idea Ryan, why dont you take a lick of your amazing product. I dare ya. It is time for these sick companies to test there products on themselves Im sure you will have the same reaction as that poor dog you had deliberatley ingest your Disgusting product.

    Now I plead to any one reading this blog to send Ryan and email or visit the site he quoted and tell this company you will not by there product due to there ABUSIVE ANIMAL TESTING!!!!


  • Lori says:

    Hi KP-

    We have used Fleabusters in our last two homes to eliminate fleas, and it has worked great! Their website is:

    It has been over eight years since Fleabusters treated our current home, and we have had no problems with fleas since a bad infestation the first spring after we moved here. I know that they recommend retreatment after carpet shampooing, but we have not had any reason to do this so far.

    We have rabbits, guinea pigs and a cat as indoor companions, so we are especially interested in flea products that are low in toxicity, as rabbits and guinea pigs are very sensitive to chemicals.

    We treated each of our rabbits once with Advantage when we had the infestation (we got the correct dosage from our vet). They had to be separated for 24 hours so that they would not ingest it grooming each other. Revolution is also safe for rabbits and guinea pigs when properly dosed and applied, but Frontline is deadly and should never be used on rabbits.

    Thanks for your informative post.

  • Blythe says:

    I just wanted to mention a product called natural defense. I have used it on my dogs for a few years now and it works great! I live where it never gets below 30 degrees in the winter and is humid and about 104 in the summer. I have never found fleas or ticks on my dogs.

    Here is the description.

    SENTRY Natural Defense products are highly effective, yet they’re safe for use around your pets and your family when used as directed. Over hundreds of millions of years, certain plants have developed highly effective defense mechanisms against potentially harmful insects. Now, SENTRY has harnessed the power of these natural botanical extracts to produce a line of flea, tick and mosquito control products that features natural active ingredients such as peppermint oil, cinnamon oil, lemon grass oil and thyme oil. The exclusive formulations that feature these ingredients are harmless to mammals, birds and fish — but they’re deadly to biting pests. SENTRY® Natural Defense™ Natural Flea & Tick Squeeze-On for Cats & Kittens kills fleas, ticks and mosquitoes for up to four weeks,

    You can find SENTRY Natural Defense products in a specialty pet store near you, such as PETCO.

    Here is the website for more info

    KP I would like to hear your opinion on this product.

  • Ryan_Noonan says:

    Hi KP, I read your post with great interest and, like you, I care deeply about the health and safety of all pets. My name is Ryan Noonan and I am in the communications department with Fort Dodge Animal Health, makers of ProMeris. Part of my job is making sure pet owners have information about our products and I wanted to share with you some details relevant to the post about ProMeris.

    Let me assure you that our first priority is providing safe and effective products to ensure the health and well being of all pets. We take reports of adverse events very seriously and I wanted to make sure you received information directly from us.

    You can link to to see a more detailed account, but quickly, a veterinarian contacted us to report six Siberian huskies and one mixed-breed dog from the same household exhibited vomiting, lethargy, pruritis (itching) and behavior change several hours after receiving ProMeris. The clinical signs reported are similar to those observed in dogs following deliberate oral exposure to ProMeris during safety studies conducted prior to the approval of ProMeris.

    ProMeris is a topical product and should be applied between the dog’s shoulder blades and directly on the skin. Please see for a detailed description of the application procedure, which is slightly different from other products. It is also important to understand, as with any topical product, there may be some dogs that are uniquely sensitive to it.

    I hope this information sheds some light on this topic. If you have questions about ProMeris, please speak with your veterinarian, as he or she is best person to talk to about your pet’s health. I also encourage you visit our Web site for additional product information.

    >>>KP’s Response:

    Hi Ryan,
    Thanks for your comment. I appreciate it. Given that ProMeris can cause such an alarming and dangerous physical reaction when licked by a dog, isn’t it a bit risky to assume that it won’t be licked just because it’s applied between the shoulder blades? Millions of households have more than one dog, who could potentially lick each other, and if ProMeris is anything like Advantage, it takes hours to dry. And given that we also have illiterate people with dogs and people with dogs who can’t be bothered to read directions carefully, plus the fact that dogs love to lick, aren’t you placing too much responsibility on consumers to make sure that the product doesn’t get ingested by their dogs? I really don’t think that such a hazardous chemical should be sold in topical form. If it’s that hazardous when ingested, it can’t be completely harmless when absorbed through the skin either. There’s no internal barrier to keep it from entering into other tissues and the bloodstream.
    Not to mention all the animals, including dogs, who had to suffer in order to bring this product to market.

  • Jamie says:

    Isn’t garlic bad for dogs?

    >>>KP’s Response:

    Hi Jamie,
    It’s usually OK in small doses, but some dogs don’t do well with it. It can cause anemia.

  • Jaclyn says:

    I’m re-reading 250 Things You Can Do To Make Your Cat Adore You, and one of their suggestions (for cats) is to make a little lemon water (boil, let it sit overnight) and put in a spray bottle. It can be used to repel fleas but also soothes cats’ itchy skin. I’m trying this out for my cats. Do you think I can use this on my dog as well? Or will lemon hurt my dog?

    >>>KP’s Response:

    Hi Jaclyn,
    I think that will be fine for your dog.

  • Bob says:

    I’m so glad you wrote about dealing with fleas! Even using killer products like Frontline, my dog still gets about a dozen a day since we’re out and about in high grass and water. I comb out the fleas once or twice a day and cut her hair really short but it’s a battle that lasts through the summer. I’ll try some of the homemade spray you recommend but my dog hates being sprayed as much as the fleas. I’ve also started adding some garlic to her food so maybe her breath will scare the fleas away!

  • Rhonda says:


    Can you give dogs a B complex vitamin that is designed for humans? My brother’s shar-pei has terrible skin and he’s always looking for helpful tips.

    >>>KP’s Response:

    Hi Rhonda!
    Yes, absolutely. For a small dog, 25 mg should be plenty. For skin trouble, I would also look at improving digestion because poor digestion can lead to bad skin. I would suggest that he give his dog digestive enzymes (Prozyme is the gold standard one for dogs) and probiotics, such as acidophilus. Probiotics are especially important for dogs who have taken antibiotics, which can kill the beneficial bacteria in the dog’s intestines as well as the bad ones.
    Finally, I would also suggest coconut oil, which is an excellent yeast fighter–bad skin is often caused by a yeast overgrowth. Coconut oil contains caprylic acid, which kills yeast. Most dogs love it too. Give 1 tsp. per 10 pounds of bodyweight per day. He’ll want to cut back a little on his dog’s diet somewhere else, because it’s pretty fattening, but it should really help.