FDA issues alert for isoxazoline class of flea, tick products

Potential exists for neurologic adverse events in dogs and cats when treated with isoxazoline class products

The U.S. Food and Drug Administration is alerting veterinarians and pet owners of the potential for neurologic adverse events in dogs and cats when treated with isoxazoline class flea and tick products, including Bravecto, Nexgard, and Simparica.

Data received by the agency as part of its routine post-marketing activities indicates that some animals receiving Bravecto, Nexgard, or Simparica have experienced adverse events such as muscle tremors, ataxia, and seizures, said the FDA in a statement. Credelio, another isoxazoline class product, recently received FDA approval.

These products are approved for the treatment and prevention of flea infestations, and the treatment and control of tick infestations.

The FDA said it is working with manufacturers of isoxazoline products to include new label information to highlight neurologic events, as they were seen consistently across the isoxazoline class of products.

These products continue to be safe and effective for the majority of animals, said the FDA, adding that it carefully reviewed studies and other data on Bravecto, Credelio, Nexgard, and Simparica prior to approval.

The agency is asking the manufacturers to change product labeling in order to provide veterinarians and pet owners with the information they need to make treatment decisions for each pet on an individual basis.

The FDA said it will continue to monitor adverse drug event reports for these products and encourages pet owners and veterinarians to report such events.

Reports can be made to the drugs’ manufacturers, who are required to report this information to the FDA, or by submitting a report directly to the FDA.

To report suspected adverse drug events for these products and/or obtain a copy of the Safety Data Sheet or for technical assistance, contact the appropriate manufacturers at the following phone numbers:

  • Merck Animal Health (Bravecto): 800-224-5318
  • Elanco Animal Health (Credelio): 888-545-5973
  • Merial (Nexgard): 888-637-4251
  • Zoetis (Simparica): 888-963-8471

To report directly to the FDA or seek additional information about adverse drug experience reporting for animal drugs, see How to Report Animal Drug Side Effects and Product Problems.

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186 thoughts on “FDA issues alert for isoxazoline class of flea, tick products

  1. My Aussie died from a seizure less than a week after using these products be very careful
    My vey actually called the company to make sure it was safe? she was 7 yrs old.

    1. Oh no my Aussie has fleas I used dawn dish soap to wash him flea powder on carpet and I got a flea collar ?I’m so sorry about your baby . Losing a pet is the worst especially when you’re amtrying to help .

          1. Any soap you put on fleas will only paralyze them for a short time. NO SOAP KILLS FLEAS.

        1. Yes, I used it on my dogs. Look on Pinterest for how to use it. I also used vinegar rinse (I believe).
          Then I bombed my house with a product from the vets office (over the counter product).

        2. Yes, but be careful! Everyone recommends it for kittens etc. It got popular because it was use to clean animals in oil spills for it’s grease cutting ability. However, there are toxic chemicals in it. Depending on health & size of animal it can be dangerous. I used it for years but stopped after I bathed 3 small kittens in it & they passed shortly after. So I started to research it. Won’t use it again.

          1. They use it on Wildlife that are covered in oil slicks to cut the grease,,not to kill fleas,,,

          2. please check more research before believing those duck cleaning commercials. They’re made by Dawn!

          3. Dawn is NOT safe to used repetitively on animals. It IS a detergent and not safe for repeated use.

        3. Do not use Dawn dish soap on your dogs it has toxins that are bad for them they only use it on the animals with the grease and oils because it’s the last result to get the oils off their first so that they can live read up on it please

          1. Dawn dish detergent is a pretty safe product. What toxins are you specifically referring to? I have used it to wash dishes for years…it can safely be used as a grease cutter and will not react with bleach, like ammonia based detergents/dish detergents of other brands will.

            I mop with Dawn and bleach every day in my pet areas…and it loosens clay dirt tracked in onthe floors well!

          1. No it IS NOT,,your comment is WRONG. It is NOT PH balanced for an animals skin,,,SMH,,,you need to research before making FALSE statements,,,,

          1. Yes this is the correct way to treat fleas!! If you need to bath them with no shampoo it will help if you can flush the stunned fleas down the drain.

          2. I like your comment. Bugs breathe thru their bodies and shampoo hhelps to suffocate them I believe. Would spraying our lawn with laundry detergent work?.

        4. Retired pet groomer…NO it does not. It merely stuns them. They will revive. I also prefer the drops instead of a flea collar. Collars tend to have harsher chemicals than the drops.

          Never use a product on a cat that is not specifically labelled for cats. It might kill them, even if its been used before.

          Water does not ‘drown’ fleas either.

          1. here’s the deal when using soap to kill fleas I would just use puppy shampoo and it won’t burn their eyes. how it works is that you have to leave it on the dog for about 5mins to suffocate the fleas but it isn’t perfect and you must wash the face a butt area first and get it all soapy. Fleas will run to those areas and hide. Shampoo isn’t a preventive and even flea shampoo is only really good for a few days it won’t prevent for 14 days like it claims to. You need to back the bath up after 48 hrs with a topical or a flea collar. I personal use Revolution I’ve been a dog trainer for almost 15yrs now and that for me works the best.

        5. when I worked with a vet to help out Dawn was all she used for fleas and it worked beautifully–with no side effects like the flea chemicals–Dawn is much safer

        6. i use a little dawn in a small container of warm water, put the container under a small light on the floor at nighttime, and in the morning if any fleas were in the house, they are drawn by the light and jump into the container and are dead

          1. Dawn has put out a warning stating DO NOT use on animals! They claimed they used it on wildlife as an emergency solution. Check it out yourself

        7. Dawn dish soap suffocates then. My mother and I use to raise poodles and that’s all we ever used on our dogs and puppies as young as 3-4 weeks old just 1 mayb 2 drops for puppies that young leave it on them for about 5 minutes massaging the puppy, cat, or full grown dog and u will see the fleas comming on top of fur for those that detached themselves. For the fleas that dont detach themselves use a pair of tweezers and grab flea as close to the skin as possible andpull them off. Also for live ticks and fleas if you can get them put them in a jar with alcohol close lid and they will die….

        8. Dawn should not be used. It has chemicals in it and strips a pets natural oils in it’s coat.. So many natural preventions! Do the research! Please!

        9. Dawn is safe and does kill fleas. It removes the wax from their exoskeleton causing them to bleed out over the course of a few hours. So even if you still see them on the animal, they will die shortly if they were touched with soap.

          Dawn is not harmful to animals. There is a lot of wrong information in this thread about the safety of Dawn on animals and the efficacy of its use in treating fleas. Probably best to call your vet and ask them rather than asking in a comments section where people with wrong information often reply.

          1. problem with DE is respiratory.
            It is made if breathed in … can cause permanent lung damage. People must use mask when using, and around. So, what is happening to the animal when they breath it ?

        1. i used DE on my dogs and it did Not work well at all. i dusted the ground and bedding areas and also applied it to their fur. Rusty somehow got it in his EYE and looked very Painful, luckily his Brother Fargo licked his eye for a few days untill it cleared up…I will Not use it again. and we Still had fleas…

        2. Yes its a natural substance but wear a face mask when you use it and dont let your pets breathe it in as it is ground up sand like and glass like particles and they can hurt your lungs if breathed in–same for your pet! Does throw it around making it like a dusting powder–then its dangerous for your lungs and your pets. They never tell you about that part of it but use caution when applying it.

      1. Please don’t use DAWN soap. DONT do what others suggest, research it!!
        Flea collars are also chemicals!!

        Dawn Dish Soap is filled with chemicals and is NOT safe to use on pets. Yes, even if your vet tells you it is safe or even if other people do it all the time with no ill effects. (side effects are not immediate with these types of chemicals, in most cases- it is long term health concerns over time that is the issue)


        I haven’t used chemicals for the pat 6 years, have had 8 dogs. Treat them 100% naturally!

    2. Aussies are commonly affected by MDR1 which is a multigene drug resistance to several drugs commonly found in flea, tick, wormers and many other drugs- especially ivermectin products. Even if your dog tests clear genetically, he/she can still be affected so all aussies should be treated as if they are positive for the defect and careful attention paid to which products are used. Many many vets are NOT informed and current on this information so don’t be surprised when they tell you they are crazy. It is a real scientifically prove genetic defect

      1. If they are MDR-1 normal/normal, then they do not have the effects of not being able to flush toxins out if their brain. I have spoken to the folks from Washington State University several times about my mutant/normal Aussie, and they added a medication to their list because of him. Any dog with the potential of MDR-1 should be tested for it. Ivermectin is only one small issue with dogs with the MDR-1 gene, then at least 95% have no problem with the small dose in medications such as heart guard, which is why few problems have ever been detected with dogs that have the potential of MDR-1.

        1. You are absolutely correct. Certain breeds are very allergic to flea meds and sedation. I have a border terrier who took an internal flea,tick med and she projectile vomited and was very lethargic. She came out of it but never again. its topical only

          1. No… There are many herding and non herding breeds effected. Here’s a link to dog breeds that are effected… More every year.


            With the affordable test to screen dogs, breeder should be testing so the likely hood of future dogs being effected gets reduced.

    3. My Border Collie started having seizures 2 nights ago it was really bad, rushed him to the hospital, they put him on Keppra, he had a very slight one last night, they told me he just had epilepsy, didnt believe it was Nexguard, my vet believes it is. He said that if it was just epilepsy they wouldnt be so frequent, he said it takes a month to get meds out of system, I still have another week or so to go, my heart breaks for your loss!!!

      1. My Collie had seizures after using frontline. I have her on cbd oil for dogs and it has been a year with no seizures. Of course I have not used frontline either. My vet told me if she had another seizure we would have to put her on medication. since I believe in natural medicine, I researched cbd and started to use it. Works well. Worth a try.

    4. My vet told me any shampoo will kill fleas. You suds up your pet, of course starting with their neck so the fleas do not crawl into ears or eyes, leave on for at least 5 minutes. The reason dish detergent or shampoos work (temporarily) is because they smother the fleas. So use a tearless baby shampoo and do the neck, ears and face first and work downward. It works and much cheaper than pet shampoos. As a former pet groomer, i used lavender tearless baby shampoo

    5. A reaction would happen within the first 12 hours if it was the meds. A lot of dogs have underlying problems causing the problem in a week…

  2. Both my Boston Terriers died cause of using the flea products from Walmart. They had seizures and then next day died. Their tongues turned grey and were very thirsty. And they lost muscle tone over night and they died in a 24 hour period after taking the pill and spray.Wish i would have known about this sooner. Oh and i did bathe them with flea and tick shampoo, but they never had ticks.

        1. Accumulation of chemicals always has detrimental endings.. not good. I think what you should have written was..
          Don’t believe what people tell you, research it. Look for toxicity in everything you expose your pets to

    1. These products specifically cannot be bought at Walmart… nexgard, Bravecto and simparica are only sold thorough licensed veterinarians so I doubt you used one of these products…. Capstar (a quick acting rapid-kill flea pill that only works for 24 hours) is sold at Walmart along with the Seresto flea/tick collar which has been shown to be very effective against fleas and ticks for up to 8 months.

        1. One of my dogs has Grand Mal seizures after swimming with a seresto collar on. He had worn it with no problems until then, went swimming twice – fitted twice. Took the collar off and no more fits.

        2. Seresto and all the others, can and will accumulate in the dogs system, like all chemicals do. Don’t believe everything your vet tells you, research it!

          1. Seresto collars provide an oil barrier on the fur of the dog or cat. It does not accumulate inside the dog whatsoever

    2. Please tell me you only used one at a time Monthly! or this is what you used to use because 3 in one day would kill any dog! Good luck!Sorry for being blunt But I could not imagine going through this You must be heartbroken!

    1. No, that is not true. Simply bathing a dog will not rid them of fleas. It will stun some of them, but they will revive. Fleas can create air bubbles around themselves to brathe, so wate doesn’t drown them. They also have a strong exoskeleton that need to be breached befor they can be killed. DE does work in that regard, but, as mentioned, its hard on the lungs.

      I’ve found the best products, and the least destructive, are pyrethroids.

      1. Oh dear that is not fair. I loved all my dogs and did everything I could just to have the vets kill them with their greed and lack of willingness. I lost one of my dogs to a seizure because the vets keep pushing their products. They are trained to make you feel like you have to do what they say or you are not a good pet owner. They killed 3 of my dogs I believe. All they want is their money of which I gave them plenty, over $ 100,000. over the course of 20 years. I still have not overcome my grief.

  3. Add Comfortis to the list as well, my dog died within four days of taking this product. This was reported but as usual got the old “oh we have never had reports those symptoms before”

    1. I have used comfortis for years. My dog is 17 and my CH cat is 9. The other one is 6. They are a little lethargic right after but they are fine, and certainly better than fighting fleas with ineffective sprays and collars.

  4. Just treated both of my dogs with bravecto/nexguard. Both are doing fine as far as fleas..but they are itching like they still have them. My copper has epilepsy and did have a seizure after treatment but cant say for sure it was because of the medicine. My bigger dog has been itchy but fine. My vet said itching is happening to alot of dogs according to customers after treatment. Started benadryl on Monday and that seems to he helping.

    1. Mine too…. finally got the fleas under control brevecto,(after 4 different topical over 8 months) but the itching is crazy. I don’t know what to do for my little guy

    2. PLEASE do your research, you’re putting chemicals on your pets. Accumulation of chemicals doesn’t show up on the outside of the dog. When it does start showing up, its too late, the damage is done. Of course its from accumulation of chemicals, and vaccines etc.
      Please DO NOT give Benadryl, dogs have died from this. Where are you getting all this horrible information from??

  5. We live in south mississippi, right on the water, in a bayou swamp. We have a larger than average number of fleas, and very few hard freeze days. We also have 5 dogs, one is very allergic to fleas. We have been using the Seresto flea collars for almost 18 months now, and find them to be the best flea/tick preventative we have ever used.

  6. Diamatatious earth works great. Search for careful applications, they can’t inhale it.. nor you.
    You can add it to their food, dogs and cats, use it on carpet or floors. Vacuum every day.
    No chemicals needed.

    1. I used Diamatatious earth on 3 of my dogs over the years and it never stopped the fleas. Applied directly. Though I hear only good things about it, never worked for me. However does keep bugs away from house.. My little guy did have a seizure after using a topical flea liquid as directed on body. Never used again. I ordered from Amazon an essential oil flea color, use an essential oil flea spray, and bathed to get rid of fleas. Then bombed the house and left for the day. Came home and vacumed everything – washed all floor coverings – finally got rid of.

  7. I had a cat and a dog die from neurological events. Both were lifelong Nexgard users. The cat was old but when my dog, a healthy ten year old who looked and acted half his age died from sudden onset of massive seizures not long after the cat, it was too much of a coincidence and I stopped using these products on my pets. He’d been having trembling, which unfortunately I just thought were from excitement, for probably 5 years or so before that but I’d never had any pets die from this kind of thing before, much less two in less than a year. I’ve not seen it since.

  8. Dawn only works for so long tho, its not a long term solution. I have recently been using “Adams” flea shampoo , I get it at Wal-Mart for about $9 for my cat and I wash her 1x a week w it and it has helped tremendously

  9. I have only used Revolution for 25 yrs & no side effects on my cats. It costs a small fortune, but it is all I trust on my babies. Works on fleas, ticks & some other issue I can’t remember right now.

  10. Pert Plus Shampoo kills fleas and is fine to use on animals. I use it on animals to young to use preventives. Kills fleas on contact. Got this tip from our vet who likes homeopathic remedies.

  11. Coconut oil kills fleas. I use it all the time. It will not hurt your dog. Has to be organic virgin 100% unrefined. I get gluten free called Vita Coco it’s a good brand. If they lick it off it will not hurt them. In fact it’s good for them. If your dog is a pancreatitis survivor I would not recommend it since has fat in it. Also I use diatomaceous earth food grade on my carpets and have used on my dogs but drys out their skin. If you vacuum your carpets, treat your dogs, and yard you can keep them somewhat under control but I just don’t use pills in my dogs systems. Seen too many dogs die from these products.

    1. Dogs with pancreatitis are fine to take coconut oil. Start with a small dose and slowly work up to the recommended dose.. that come from a few holistic vets

  12. I use seresto collars sooooo worth it…also if it is a infestation you can use capstar, one pill and they are gone, we use those in rescue when we get dogs with lots of fleas…then do the dawn shampoo and joy lemon works too just leave it sit on them for awhile to kill the fleas…so sorry to hear all these stories of pets dying from these chemical treatments…

    1. Pets dying from these chemical treatments? What do you think sparest is?
      So typical, This explains why so many rescue dogs immunes are so weak and they come to me to be healed!, from all the crap they have to put up with.. seriously surest collars are a known chemical which has injured many dogs. To say that your dog is fine, is not true.. its a walking time bomb

  13. Dawn is not the best option, it is very drying on the skin. It may cut grease and help when mixed with vinegar for skunk stink, but it’s not meant to be used for regular flea baths. Ask your vet what is best for your pet. Don’t go off Pinterest or other interweb sites.

  14. My healthy Maltese and Yorkie passed away 12 hrs. from each other after wearing a Seresto flea collar for only 5 days. I would love to get Bayer to admit their product is not safe. Autopsy showed nothing but healthy dog.

  15. My Manchester Terrier, Audrey, had seizures after taking Simparica. I returned it to my vet, who gave me credit, buf they said they knew it was on the recall list with the other 3. It happened about 3-4 months ago and she has had 2 more seizures but not as severe. Thankfully our flea season has not begun so I have not given anything else. I will start her 1 March on Revolution. Her cognitive ability has decreased and was 8 years old when the Simparica was started. It has aged her immensely.

  16. Last year I fed fed bug off garlic from Spring time. Worked great on dogs and horses. Once the hurricanes came thru I had to use a flea treatment in sept We also have bug man spray our house and yard every 90 days. When we walk in woods and on the beach I will
    Use a littke skin so soft on their ears.plus a bug bracelet on their collars. We walk everyday so I know the garlic is good. Plus if keeps flies off of horses

  17. We believe our dog began having seizures due to 1 dose of Bravecto. We spent a lot of money to have all the tests necessary to prove it wasn’t anything else. Those seizures eventually took his life after months of tests and seizure medications.
    Please educate not only the consumer but the doctors that are selling this to people to give to their pets. We were just doing what we were told by our vet to do….
    We now use Springtime garlic in our newpups food and have not had any side effects.

  18. I just bought these two products to see how they work.
    They’re sold by Grove, a reputable online store.
    KIN & KIND brand: ‘Flea&Tick spray’ , AND, Flea&Tick Shampoo….no parabens, no sulphates.
    We’ll see how that goes.

  19. I have 2 pugs and a boxer. I give Heartgard and Nextgard to them but I cut the pills into 4 parts and give it to them in a 4 day period meaning 1/2 a pill twice a day for 2 days for the Heartgard and 2 days for the Nextgard.

    Even with their vaccinations, I will take them to receive one for each visit. It costs more to visit the vet each time but I am not taking any chances for seizures.

    1. With my shelties I don’t give anything too close together. I give Nexgard and then 2 weeks later Heartgard for the heartworm. Same goes for any shots they may receive. At least a month between rabies and anything else they might be getting. I had a pet buyer bullied into giving all shots together and a perfectly well 5 yr old Sheltie died due to shock.

  20. Before anyone starts pointing their teacher finger. I was typing faster than my brain was think. So I meant to say…. NO SOAP KILLS FLEAS. THE WATER ALONE WILL PARALYZE THE FLEA AS WILL THE SOAP. ANY SOAP.

  21. In a discussion with several breeders in Brazil, we detected a reasonable decrease in the fertility of females and males. Boxer litters with 8.9.11 puppies now cost to appear. average of 3 or 4 has been frequent, using the same techniques of mating, natural or insemination. In the great majority, both animals made use of these products, sometimes only one of them. But they were always subjected to such chemistry. Can it also be interference to be studied? What do you think? Do you detect the problem in your creations?

  22. Sorry, comments, regarding not using something because it is full of chemicals and using something else because it is chemical free or 100% natural, i.e. safer, are a major pet peeve for me.

    You ARE using chemicals to treat your dogs. Sorry, everything is composed of chemicals and can be toxic. The type of exposure, length of exposure, and toxicity of the substances all matter. Even holistic, 100% natural substances have some level of toxicity. Doesn’t matter what you use.

    Indeed, do you research about the chemicals you use and use them with due care and diligence. Remember, some of the claims regarding safety/toxicity are over hyped. Apple seeds do indeed contain compounds that metabolize to form hydrogen cyanide. Hydrogen cyanide is a highly toxic compound. But, a person would have to eat several hundred bushels of just apple seeds in one sitting to reach toxic levels.

    Full disclosure: my black lab developed seizures after flea treatments after several years of being treated routinely. He died as a result of a seizure.

  23. My dog would always have seizures and my brother-in-law’s dog died from flea meds. I’m so happy to say that I have found a natural product that fleas can’t stand it’s a powder that you put on their food that actually taste very good they love it I feel so much better not poisoning my animals. It’s dr.bob goldstein’s Nature’s protection by Earth animal. it’s a daily herbal internal powder that is spread on their food. The ingredients are alfalfa garlic blue green algae spirulina kelp papaya neem,Nettles and Hawthorne. Please and

  24. Used flea meds on my one year old dog, I immediately took him off them when he started having seizures almost daily right after I started the flea meds. He is 8 years old now and still has seizures about twice a year. I told my vet that the flea meds were making him have seizures and she looked at me like I was dumb and said she had never heard of them doing anything like that before. I told her she should google it and look at a few videos!

  25. There is an excellent product using citrus, mostly orange, peels. Works great and won’t harm your loved one! d-limonene from the peels does it. Amazon has it!

  26. This is why I use Flea Away its a herbal chewable pill every day and its $20.00 for a 100 tablets..I have been useing this for 2 yrs now and I have three small dogs..www.chewy.com
    I love this website..

  27. Use food grade diatomaceous earth. It is natural and safe for pets, humans and environment. Just read directions. It only cost me about $14 @ Blains Farm & Fleet. Works great and lasts a long time.

  28. I will also recommend using Borax as a house product to reduce the population of fleas…. you can sprinkle it in carpets and the floor. vaccum and reapply. It dehydrates fleas(all life stages), so you can break the life cycle.

    Most pets do not have major reactions to it… but that said…. don’t let them have extensive exposure.

    Some helpful treatment options here.

  29. Four years ago, my then, 11 year old mini doxie had a stroke. Since then, he would have focal seizures and his health gradually deteriorated. At 15 1/5 years old, about a month ago, he began seizing and we believe he had another stroke. We rushed him to the ER where we had to make the painful decision to but to put him down. He’s been on Nexguard for several years…now I wonder

  30. My Fox Terrier began howling and barking and was in horrible pain after taking an Elanco product. She then began having seizures and had to be put to sleep. She was 15 1/5 years of age.

  31. Oh heck might as well toss this in there for those who believe Dawn kills fleas. IF, and again IF it really did kill fleas, don’t you think the same people who show the proven positive effects on cleaning oil off birds when used properly and used only ONCE, would be showing every breed of FIDO being bathed in Dawn and fleas leapin’ and hoppin’ on a moonshadow? And from a pure common sense standpoint, soaps and detergents designed to cut greases and oils of any kind just ain’t gonna help skin of any animal when bathed in it. Go ahead and start showering with Dawn everyday…let me know how that works for ya.

  32. I am beyond angry. My Samson has neurological problems after being dosed with Revolution which contains this horrible chemical. I plan on writing letters and doing whatever I can to get this off the market. Funny they say it can cause these horrible side affects but FDA say it’s safe. What a bunch of lies!!!!! If I could post pictures of before and after you would see what this has done to my 8 month old cat. It is truly sad

  33. Years ago I stopped using any chemicals on my dogs… Maybe I am fortunate, but I have yet to see a flea on any of them… An occasional tick or two in ten years… Try treating the outside of your home regularly with Diatomaceous Earth (Food grade)…

  34. I don’t use any flee projection on any of my animals …granted my dog only goes out to walk and I hardly have her outside she uses wee wee pads…. I have no issues with fleas and don’t want to use poisons on my pets……

  35. Apple cider vinegar, wipe with soaked cloth into skin for cats and dogs-3x week, no fleas or ticks two years now…when they lick it is good for their gut system.

  36. I’ve used bravecto for 3 years now no issues on 15 dogs. It’s also the only flea/tick prevention that works where I’m at I’ve used and tried everything else including natural treatment and nothing but bravecto has worked.
    I’ll stick to what I use

  37. Baking soda and and apple cider vinigar kills fleas instant ly on your dog get 2 liter container fill with water at bath time add little over one fourth cup backing soda to water and at vinigar when it starts to foam pour on dog then rinse dog off. Ive used this method and it works

  38. Cripes.. no dawn, no this, no that , it will kill, it will poison, no garlic, no oil,,,,,,,,

    Ya’ll should just stop for a minute and read the posts. No one is helping anyone. Good Lord we are so fecked..

  39. I was giving my Shih Tzu Nexgard and worried about side effects but didn’t see any. I used all the pills and don’t think I’ll give her any more after reading the article. Thanks for posting it.

    1. I used coconut oil on my small dog and the fleas were gone…and her skin was soft…all itching stopped. Now I use it on her every few weeks to moisturize her skin and kill any fleas. I was amazed how quickly it worked. It also repels them. Google it.

  40. Tried free sample of Brevecto on 75 lbs pit mix…she developed bleeding from her gums and bruising on stomach and chest. Did not realize what it was until weeks later when I read side effects on line…never again!

  41. Some of the stuff I’ve read here is absolutely amazingly DUMB!
    There have been warnings for these products about quite a while regarding seizures.

    Any Citrus based soap will kill fleas but the goal is to prevent them which these soaps will not do.

  42. Fleas do not live on animals. The animal is the restaurant. Unhealthy animals are afflicted more than healthy. Fleas live in the environment and are cyclical. Their eggs can go dormant. If you do not rid the environment of the fleas, their larvae, and their eggs you will have constant reinfestations.

  43. Put food grade diamethous earth in a spreader on your lawn and you’ll never have to worry about fleas or ticks again and it’s safe for children and your pets to be around. The molecules are sharp and puncture the exoskeletons of ants, beetles, grubs, ground wasps, fleas and ticks. We started doing this last year and for the first time in almost 20 years, no dogs are itchy, no ants in my house, no grubs chewing up my lawn.

    1. Diamatacious earth becomes useless once it gets wet (read rain, heavy dew). I am curious about nematodes. How long do they continue to work. I want to spray a wooded area we walk in daily.

      1. Nematodes commonly parasitic on humans include ascarids (Ascaris), filarias, hookworms, pinworms (Enterobius), and whipworms (Trichuris trichiura). The species Trichinella spiralis, commonly known as the ‘trichina worm’, occurs in rats, pigs, bears, and humans, and is responsible for the disease trichinosis. I do not understand how Nematodes would be something you’sd want to use……please clarify, thx

  44. I take it that the majority of people that compare using Dawn as a safe alternative to rid your pets if fleas . These products do more harm than good . Especially the woman saying …Quote “I use it on my dishes for years and I haven’t gotten ill “. Dishes are not living breathing animals !!! Animals skin absorbe the chemicals through thier skin and into their blood stream .These foregin Toxins are filtered through your pets , Liver and Kidneys . It won’t happen over night but your putting your pets in danger . Please Do The Research !!!! Retired Chemist and Animal Advocate

  45. Has anyone had a bad reaction with their smooth collie? I have given my female smooth collie Simparica for about 4 years. She has been totally fine and flea and tick free. I live in an area where deer ticks are very prevalent. My dog is exposed to tick infested areas a lot because she is involved in herding and tracking.