I saw ads for a new flea and tick insecticide on Hulu recently, and was curious about the ingredient they were using. The following post outlines the research I did on the product, and a related one I found during research.

About the product

The makers of Frontline have created a new chewable product called NexGard that can be used to repel fleas and ticks. It is similar to another product called Bravecto, also a chewable designed by another company also used to repel fleas and ticks. Both products contain a chemical derivative of isoxazolines, which are derivatives of isoxazole. All are part of the same chemical group the better-known insecticide fipronil comes from.

About the ingredients of this flea and tick preventative

The active ingredient in the flea and tick product NexGard is called afoxolaner, and the active ingredient in Bravecto is called fluralaner. They are similar chemicals, as noted above. Afoxolaner states the following efficacy:

Fleas and ticks must attach to the host and commence feeding in order to be exposed to the active substance. For fleas ( C. felis), the onset of effect (death, >95%) is within 8 hours of attachment. For ticks, the onset of effect (>90%) is within 48 hours of attachment. (Source)

If you are concerned about some tick borne diseases that may be transferred in less than 48 hours, you may want to consider other forms of repellants. This product is also not recommended for dogs who have a history of seizures, and recommends consulting a veterinarian before using with breeding, pregnant or lactating dogs. The study that demonstrated the efficacy of the product was funded by the manufacturer, something to consider in the decision making process. In other words, you may want to consider anecdotal evidence as well.

Safety of afoxolaner and fluralaner

Unfortunately, there is very little information on these drugs. Afoxolaner was recently approved in 2013, and most of the information available online points back to a study that was sponsored by Merial who patented the drug. Not only was the trial done on dogs with afoxolaner run by the manufacturer (Merial), but the trial done for Bravecto was performed by employees of Merck who sell it. Because both studies were conducted or sponsored by the companies that had vested monetary gains by them producing a positive result, I do feel that either are worthy of close study or consideration.

This, of course, is my opinion only. I do not have a lot of trust in large corporations paying for their own safety studies in order to bring a new drug to market – of which there is significant monetary gain as described here: “Under section 512(c)(2)(F)(i) of the Federal Food, Drug, and Cosmetic Act, this approval qualifies for FIVE years of marketing exclusivity beginning on the date of the approval because no active ingredient of the new animal drug has previously been approved.” (Source). Essentially, generics can be made after patents expire and this means that such companies create new products that only they can sell. Companies need to keep patenting new drugs to have this market advantage.

But what we do know is afoxolaner (NexGard) and fluralaner (Bravecto) are both part of the isoxazoline chemical class. They are commonly used against parasites, and is in the same group of chemicals as Fipronil that is widely known and understood to be a carcinogen. Chemicals in general can lead to suppressed immune systems, and suppressed immune systems can directly lead to problems like immune-mediated disease and cancer. In other words, it’s best to proceed with great caution when approaching unknown chemicals.

I do agree with the veterinarian who states in this article:

Consumers in general, and the pet-owning public in particular, need to be more mindful and questioning rather than trusting what they are told by manufacturers and our government regulatory authorities.

Because afoxolaner is part of the same class of chemicals as fipronil, and has not been independently or widely studied or on the market for long, I personally believe that great caution should be used before putting this chemical into your dog’s bloodstream.

In summary

Unfortunately I wish there was more concrete evidence that I could point you to about these products. They are new, and the only science I can find in relation to their efficacy and safety comes from, what I personally feel, is a highly conflicted source. Therefore, I can only present that the chemical is related to one that is known to be dangerous, but I can’t say with any certainty it is dangerous as well through related (unbiased) study or anecdotal evidence as the product is so new.

I do invite you to weigh in your own concerns, or share any anecdotal evidence you have experienced or found. I don’t doubt that the product could be quite effective, but I always do caution people to carefully consider the long-term risks of any chemical – especially new ones that have yet to prove themselves – that is used regularly and directly enters the bloodstream and can suppress the immune system or cause issues that we just don’t know about yet.

UPDATE: There are two very active groups on Facebook about these two drugs. There are regular postings added about dogs who are experiencing similar and severe side effects not long after taking these drugs, suggesting there may be a link between the two. Do remember that this is anecdotal evidence, but it can be useful to help arrive at a decision provided the limited studies and limited time the drug has had on the market.
Bravecto group
Nexgard group

Note: I am not a veterinarian. Please consult a trusted professional before administering any of these or similar drugs to your dog. If you are not sure, ideally seek a vet without vested interest in a related purchase.

About Author

Jen deHaan is graphic designer, small business owner, and dog person living in Bay Area, California. Jen enjoys learning about dog training and behavior, and has taken several courses and seminars since 2010. She also contributes articles to leading websites, such as Victoria Stilwell's Positively . It all started with a great dog called Mikey (aka "dude"), loved and lost but remembered forever. Jen also runs a freelance business focusing on graphic, web, and UI design at FoundPixel, and a small business creating hand crafted dog products at Stylish Canine.

  • Patti

    I just suffered a loss of my beloved bearded collie at the hands for Bravecto. Bravecto is a KILLER! DO NOT GIVE to your dogs! I had a 4 year old bearded collie that went to the vet on Wednesday 6/3/15 was GIVEN A CLEAN BILL OF HEALTH, prescribed Bravecto and then died less that 24 hours later after taking it! He started to cry out and then collapsed, one of my sons started cpr on him and he was rushed to an emergency clinic only to be pronounced dead shortly after his arrival. Please, please, please DO NOT GIVE BRAVECTO IT IS A KILLER!!!!!

    • Patti, I am so so sorry for your loss! I just saw what I believe to see your story (Duncan?) on Facebook. Thank you SO much for getting the word out about what happened – it is sure to help others make a good decision for their dogs, and you could be saving many lives in the process.

      My hugs to you. Sudden losses are absolutely one of the worst possible things to experience. Know that my thoughts are with you at this time.

    • Dawn

      I just got a dog from the vet I go to that was rescued from a very abusive home and he is very malnourished. They gave him Bravecto yesterday and today he has had diarrhea 7x and is lethargic. Is there anything I can do to counteract this? Please help.

  • Marie Aussie

    Well too bad I just found this article. I went to the vet this morning for my Blue Merle had developed hot spots and was biting herself raw on the hind end. I asked for Temeril-P and the clerk gave me this sales pitch o Bravecto. $52.00 dollars US and lasts for 3 months. I gave it to her as soon as I got in the car. I get home and start reading about it and find that it is new, and at least 28 Beagles died that were 9months old from their form of testing. They fed 8 week old Beagle puppies this Fluralaner for 6 months and afterwards they euthanized them and did post mortem studies.
    First of all, why was it necessary to euthanize these pups? 2nd of all, 9 months is hardly to see what the chemical does to the dogs long term, as in cancer.
    The clerk did NOT tell me to offer it with food either, so my Aussie got this on an empty stomach. You can bet I will go back with this information to the vets office, my dog will not receive another dose of it ever. Tomorrow I will be on my way to the Holistic store to find a detox herb for my Aussie.
    Thank you for this article.

    • What a tremendous thing you did looking into it though, despite a dose. I too bought Trifexis after a pitch a few years ago. I was inches away from giving it to the dogs, then realized I should maybe read into it more (this was back when I recalled reading it was “so safe”). Dug into it a little, and started hearing the horror stories. Many more of them now…

      It’s such a scary world we’re in where our dogs are the scientific study never run for long-term safety. Efficacy – sure. But safety doesn’t seem to be part of any study run before these drugs become FDA approved. Then the long term you mention… nothing at all. Is anything run about bioaccumulation? How it affects the immune system over time? What it may trigger or influence? Considering the related Fipronil is a “slow acting poison” do we even know how fast or slow these chewables may poison?

      Anyway – best of luck at the Holistic store and for the detox. Look into Chlorella – they have dog versions, but you may prefer human “Clean Chlorella” (it’s produced in Korea in indoor tanks, which reduces contaminants). Anyway, it’s quite proficient in detox for humans and I’ve been reading into use on pets where it’s also safe.

      Take care and wags to your Blue Merle.

      • Marie Aussie

        Thank you for your kind response. I started cooking for them last Sunday, It does not cost that much to buy organic. If you have any recipes to share I would be grateful. I started with organic chicken, sweet potato, broccoli, rolled oats, flax oil and eggs.

        • Fantastic!! I’ll paste the home cooked recipe we received from our holistic vet years ago. (Right now the dogs have a raw grind diet that’s mostly meat/organ/bone ground in with herbs and garlic).

          The one thing we noticed is one of our dogs does a little better without sweet potato, which can sometimes make them itchy I read. Only some dogs though.


          40 lb dog, per day.

          10 oz of meat (10% organ meat)
          10 oz of cooked mixed vegetables, esp leafy greens
          5 oz of either rice, barley, oats, sweet potatoes
          1.5 tsp of olive oil
          0.8 tsp calcium
          0.4 tsp salt substitute (ie: No Salt)

          Add daily (per directions):

          Fish oil/omegas
          Herbal multivitamin


          Vegetable options:

          carrots, green beans, peas, romaine
          (smaller %) spinach, broccolli, red pepper, celery, banana, apple, blueberry

          See also: http://www.diamondpaws.com/health/barfveg.htm

          Others healthy things you can add:

          Boiled eggs or even raw egg
          Cottage cheese
          baked yams

          Note: it’s important to change up the ingredients (different proteins, different vegetables), it’s good for the dog both mentally and physically.

          Vegetables should be steamed and run through the food processor so they are easier to digest. We ended up getting a huge steamer and food processor to help with this.


          Hope this helps! There are a ton of options out there. The main things to watch for are calcium (as it’s so vital), and be cautious not to focus too much on one veg (ie: some are not good in larger quantities, like broccoli or spinach).

          • Marie Aussie

            My dogs love Chobani plain yogurt and Almond milk, are these sufficient calcium? What are you using for salt, and I heard kelp was good for them in small does too.

          • I’m not too sure about the amount of calcium in yogurt/almond milk – we were adding it manually in the above recipe (in their raw grind they get it through bones). You could get calcium for dogs and just mix it in to ensure the proper amount is consumed, it’s very inexpensive. And you can of course still provide the yogurt. One thing to watch in yogurt are hormones etc. since dairy comes from pregnant cows (sigh, this stuff gets so complex).

            Our vet’s diet included the No Salt, but not regular salt. We did however provide a multivitamin that had the required daily nutrients (this was years ago, I forget which one we used). Dogs need very little sodium and can get it from other sources too (there is often an excess in treats, including many human foods commonly given as treats, etc). If you don’t use a daily multivitamin you may want to consult with a vet about the exact supplements you will want to provide.

            I too have heard about kelp being fantastic. We’re just starting a bunch of new supplements (I’m adding them slowly) – next up for us are Turmeric/coconut oil, and Chlorella. After I may have to look into kelp :)

          • Marie Aussie

            Hi Jen,
            Thought I would pass this on to you for the pups, I found it at the Vitamin Shoppe for joint mobility with turmeric in it. Called Mobili-T by LifeSeasons: Collagen Type II, Glucosamine, Chondroitin, MSM,. Turmeric

  • jessica

    I have a 2yr old Golden Retriever and we have battled fleas for three weeks now. He is itching himself constantly, causing black scabs all over, and I can see flea eggs on him. I have given him organic flea baths, dusted him and our home with Diatemaceous Earth, used Purification oil on him, as well as top grade cedar/lemongrass/lavender sprays on him and nothing is working. I vacuum daily, flea comb, and he is still miserable. I called two holistic vets in our area, Portland, OR, and both recommended Comfortis or Afoxolaner, being they use “organic pesticides, the same pesticide that veggies from farmer’s markets use” Literally, that is what they both told me! I broke because I was desperate and my pup was miserable and gave him Afoxolaner. Now I’m panicking. Can anyone give me pointers on what they are using for natural non-pesticide flea prevention? Our area is humid and hot and this summer is supposeed to be off the charts heat-wise.

    • I think one of the issues is that the pesticides are also quite controversial in organic food circles too!

      I’m so sorry about the shock – try not to panic too much, because I always feel it’s better to know about something sooner rather than years and years later you know? Regardless, there are other things you can try. Here are a few ideas for you to look into.

      1) Food. The first and foremost thing to consider is diet, I feel. There is a lot of evidence around raw and/or home-cooked meals greatly influencing (reducing) pests. Has many other benefits, including related ones, like supporting a strong immune system that’s very important for all aspects of health. If finances are a concern, look to meat co-ops or even local hunters who have game to sell. It’s amazing what’s around if you dig a little, and it can almost become a cheap way to feed a dog.

      2) Garlic and brewers yeast. Very inexpensive (I use BugOff garlic for dogs from Springtime and Brewers yeast from Amazon – but there are many, many options), and can be combined with food.

      3) “Tags” like ShooTag or related ones. I’m trying a new one from Only Natural Pet tomorrow. I’ve had anecdotal success with them. No claims to understand the science, and it could be coincidence, but I have had personally seen two cases in my own house where I’ve had fleas on the pets and added the tags and no fleas on them later in the week that lasted for months (my cat doesn’t get raw/homecooked due to IBD so she needs tags for sure). I was recommended these tags from a pet store that reports many customers swearing by them – was kind of surprised to see any result, but hey. No chemicals. I use them during flea season.

      4) Try other sprays, such as CedarCide (I just ordered based on reviews – haven’t tried it yet). Can help with fleas around the house, and apparently safe to use directly on pets. You may need to find the right one based on your dog and what you feed.

      And of course, with all of these keep up with the regular washing and DE or cedar sprays can help. When going chemical free, I do believe a holistic (ie: diet and supplement being of utmost importance, spray, washing, tags etc to aid) approach really helps – and although it is certainly more work, the payoff is a healthier dog without needing to worry about long-term chemical use.

      For all of the above, remember it takes some time for the body to adjust and if using tags it takes at least a few days to take affect (apparently). Relying on the food for help can take a bit longer to let the body shed any toxins from the food and strengthen the immune system and so forth (basically, become the kind of body a flea doesn’t enjoy hanging around on).

      Best wishes.

    • georgehollister

      None of those non-pesticide flee control alternates work. And urban fleas are becoming immune to the topical pesticide treatments. Try the once a month pill. For me, it works well. I have given it in combination with heart worm preventative and round worm preventative.

      • “None of those non-pesticide flee control alternates work.” That is simply not true as a blanket statement. The protocol I listed below does not involve pesticides, and has kept fleas and ticks off my dogs for over 4 years and possibly mosquitos (as their heartworm tests have all returned negative). I am 100% sure they have been around tons of fleas and at least a moderate to high level of ticks when we’ve been hiking, and they do not have any on them. My friends dogs have returned from the same hiking trips with many ticks. A pesticide free protocol does involve a multi-faceted approach and diligence, but it is certainly possible and DOES work in at least my experience over the years with the dogs I have. I have spoken with many others in other regions that it has worked for as well (also with a high flea/tick environment – hot, humid, standing water etc). Not to mention, all of those chemicals depress the immune system which is the first line of defense against cancer and many other serious diseases. Oh, not to mention – heartworms.

        • georgehollister

          If they work for you, that is great.

          • It is! And that’s why I write, to provide alternative options to try before resorting to more dangerous ones :) I myself never knew about what the options are before researching a lot, as every vet I’ve had pushed me toward poison.

  • Jane Calver

    Hi, my sister’s vet in Erin , Ontario just recommended both Revolution and Bravecto for her 11 year old Lab for ticks. After I read the study that was done in Ireland for the drug company and a few horror stories( not necessarily substantiated) I would not feel safe in using it. I have a large Airedale and we now have ticks in our area. If these chemicals are safe for dogs, why are they not recommended for people who are susceptible to Lyme disease? Makes you wonder doesn’t it?

    • Absolutely!!! I’ve always wanted to respond to those who say “sometimes you just need chemicals” to ask why they don’t put a top spot or chemical collar on a baby when hiking in the woods then…

      My first vet recommended Frontline just because my dog was itching – no fleas (I told him that too, thoroughly checked and watched for fleas all week). Didn’t suggest looking into allergies or skin problems, just recommended Frontline over the phone no exam :( I was a new dog person, and didn’t know any better, so unfortunately I followed his advice.

      • georgehollister

        Urban fleas are becoming immune to Frontline, and it’s other competitors.

      • Antoinette le Roux

        Hi Jen,
        You say that you have ‘unfortunately’ followed your vet’s advice by using Frontline. Were there any adverse reaction? I have to know, because that is what I have bought to put on my pup. I have not yet had any problems with Frontline spray with any dog, but have also not used the spot on version because I do not trust it. I have bought the spray again, but if there is any chance that my pup will react to it, then I’m throwing it away!

        • Yes, it’s probable I ran into side effects with the drug – but side effects (and serious ones) are very common with Frontline in general. My dog died from IMHA (he was on Frontline and Heartgard, and we ruled out other possible causes of the disease), and although I cannot make a direct scientific link there is a lot of anecdotal evidence in the IMHA community that links the two. And for that reason, and many others, I avoid all flea and tick pesticides in my dogs’ blood streams. I encourage you to read into Frontline reactions online from other dog owners. Note that Frontline is in the same class of drugs as Bravecto (basically a small chemical derivative to form the drug, I suspect for patent reasons).

          • Marie Aussie

            There is a spot on Facebook started by a holistic vet on bravecto and nexgard. A link to report side effects to the CDC as well.

          • I have linked a couple of the Facebook groups in the article, but very happy to link any others that are out there. Feel free to post the link here and I will add it to the article body. Thanks!!

          • I think those might be the ones I link in the article, but if not please feel free to add a link here. Thanks!

  • georgehollister

    How does Fluralaner work? What was involved with the studies performed? These studies should be available for scrutiny, and reproducible. Understanding how the drug works is important, and known. This pesticide is active in the dog for three months, and has no ill effects on the dog? That is interesting, and worth more than a superficial review. There are people bitten by disease carrying fleas all over the world, why not give the drug to people?

    • Good question, but possibly more the case for ticks than fleas. If the tick borne diseases are so damaging to children (which they are), why don’t they develop a top-spot for babies? My hypothesis is that it – if like what are put on dogs – would never pass tests. Or, would need to be tested much more thoroughly than they do for dogs. We do need to understand the risks of these drugs in many, many more scenarios (dog ailments, mixed other drugs, breeds with certain genetic traits, etc) and for a longer period of time than these tests have been run. They need to look at how it affects the immune system. People’s pets shouldn’t be a science experiment. And since they are, it makes sense to share these anecdotes so people can make a better more informed decision before choosing to use these products – and I do hope that vets would also be encouraging this and diligent research before taking on a pesticide that their dog will have in their system for many years as part of a cocktail with other drugs/pesticides in their system for years.

      • georgehollister

        Since posting I read some stuff from other sites. Fluralaner kills tickets in 48 hours. 48 hours is the minimum time estimate for a biting tick to transmit lyme disease. So it is unclear if this treatment prevents lymes or any other tick transmitted disease. By the time I find a tick on my dog, more than 48 hours have gone by. And I have had inconsistent results from various tick collars. If they get at all wet, they are useless. But fleas transmit diseases like plague and another bad one that slips my mind right now. People in poor countries, living in flea infested conditions, might benefit from the treatment, if it kills the fleas. The pesticide apparently kills mosquitoes as well, but has minimal application for obvious reasons. Dangerous to people? It needs testing. It is intriguing that Fluralaner can stay in the dog’s system for three months, with no observed affects. This is also a new generation of insecticide that was supposed to be used in agriculture first, but ended up being used in pets, first, instead. Unusual. The insecticide focuses on disrupting a specific metabolic system unique to insects. I expect to hear more about it’s expanded use moving ahead. It might take the place of organic phosphate insecticides in agriculture. I emphasis, might.

        • I actually do note that in the above article. However, I also note that there are some diseases that transfer in less than 48 hours, and this pesticide is not always effective in 48 hours. That’s why attacking the problem before those 48 hours have passed is way more effective. And yes, as mentioned in the above article and linked data sheets, certainly understand and have explained what these pesticides are intended to do. The problem I’m discussing is what they also do to the system, and how much is not known because it wasn’t studied. Look at the studies of drugs now known to be really dangerous, and how they were once considered “completely safe” because of short and incomplete studies and quickly released drugs for patent and profit reasons.

          As also noted in the article and above comment, just as dangerous to dogs is the ongoing suppression of the immune system – this just one major contributor to the assault placed on it factoring in all the other things they (and we) are exposed to and/or eat. A suppressed immune system leads to cancers, auto-immune disorders, and a host of other ailments. Over half of ALL DOGS get tumors, and it’s the cause for over 50% of senior dog deaths. Over half. That’s why I consider these pesticides dangerous, and don’t doubt for a second they cause many of these problems.

          I’m certain this stuff will be used more in the future like you say. Would be shocked if it wasn’t. After all, we can guess it’s primarily about profit before the patents expire.

  • susan

    Hi, I started a Facebook group called Does Bravecto Kill Dogs so people could come together and report side effects from this drug. The stories in less than two weeks are heartbreaking. Including myself, approximately seven stories of people that healthy dogs die within a short time of taking the medicine. And many other stories of horrible side effects. I urge you to check out the postings yourself and share this information any way you can. Thank you

  • Patti Winter

    11/2015: Center for Veterinary Medicine Adverse Drug Event Report, for Bravecto. 22 pages of adverse reactions including deaths: http://yourpetsneedthis.com/wp-content/uploads/2015/11/Bravecto-fluralaner-ADE-report.pdf

    • Millie Padin

      Thank you , I will not be giving my furbabies this drug, let them deal with the fleas and other preventive measures,

  • Brenda

    Hi, I live in South Africa and have or rather had 2 beautiful border collies until my local vet talked me into Bravecto. I lost my very healthy 3.5 year old male with a bout of diarrea followed by so called IMHA within the month. My boy who was very active and a great jumper started weakening in his back and was less eager to jump and walk. Only on reflection after his death did we realise it started just after taking the Bravecto.
    My 4 year old girl is really struggling to walk and is also quite lethargic.
    The 3 month period runs out at the end of Jan and I can’t wait to stop this madness. No more big drug companies or pesticides for us.
    My neighbour’s dog has also started seizures after taking the drug.
    This might all be coincidence but I am definitely not convinced.

    • Hi Brenda,

      I’m sorry for your loss. I’m not too sure if you saw my posts on IMHA on this site, but I also lost my dog to that disease. I do suspect either vaccine or preventatives as the trigger (he was on Frontline). You can find one of the posts here http://dogthusiast.com/2010/10/11/what-i-learned-from-losing-my-dog/ and the other here http://dogthusiast.com/2010/11/30/the-story-of-mikey-our-dude-for-celebrate-shelter-pets-day/. Not using these kinds of drugs and pesticides was also the first thing we did after experiencing that terrible, terrible disease which is believed to be triggered by them.


    • Jane Lister

      Have you reported Brenda and if you have not already done so please join our page and tell your story. I am worried that the MDR1 gene might be responsible for some deaths / reactions as the testing was VERY limited. Just 16 dogs and half got the Bravecto and half a placebo. I am unable to find any other testing mentioned than this one test!

  • DogLover

    Reporting in on another dog death. 1 year old healthy two year old, two months sucumed to Kidney Disease after Bravecto/FLURALANER. Other dog is showing increased levels on blood work up. Have a blood test done immediately if you have given your dog Bravecto.

  • Bella

    To understand what you are giving your dog with these two drugs, you must understand the industry that manufactures them. Sadly, unethical, and unaccountable once adverse affects are reported in. Merck manufactures Bravecto’s ( fluralaner ). Sadly I did not know the history of this company, nor did I do my research on this drug. Out of three dogs, one has died, another blood work up affected, and one appears to be unaffected. The one that died was under two years of age. Snopes is not a good rebuff for the reports of deaths, for they simply have a vet who believes in this product give his opinion. Snopes has lost credibility with their listing of this as a hoax. From their Vioxx deaths, to now their MM vaccination fraud, gardasil vaccine, and the finasteride side effects men face, no one is safe… Not even our dogs. Do your history on this company before you rebuke the deaths as a hoax. Sigh. She’s gone… this is so real and unnecessary.

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  • Jane Lister

    It is no longer just “anecdotal evidence”. We now have Freedom of information reports on the reports cases in the USA in the 19 months since Bravecto was released there. 5319 reports and 164 deaths for Bravecto. 7155 reports and I think it is at least 100 deaths for Nexgard.





  • Patti


    The deaths and side effects after dogs have been prescribed the oral flea and tick chewable Bravecto is mounting. Now there are even reports of adverse reactions in humans. In the newest Center for Veterinary Medicine Adverse Drug Event Report for Bravecto released in 1/2016 there are 29 pages of adverse reactions including 106 new reported deaths on top of the 54 from the report that was published in 11/2015. The new 2016 report also includes adverse reactions reported in humans. Since awareness was first raised in June 2015 from a FB post that went viral and then again in Aug. 2015 when the group Does Bravecto Kill Dogs? was started there is a total of 5319 adverse reactions which include deaths in both of the CVM ADE reports, the first was released 11/2015 and the 2nd one 1/2016. Links are provided below.



    The group Does Bravecto Kill Dogs? offers additional information, how to report any reactions or deaths along with stories from pet owners . There are vets and vet techs in the group as well as hollistic vets who provide safer alternatives and the group members offer support: http://www.facebook.com/groups/411371212394679/

    Please feel free to share!

  • Antoinette le Roux

    I can personally testify to the drug Bravecto being very dangerous to dogs. My brother’s 5 year old Labrador female was one of the most healthy dogs that I know. Never anything wrong with her. After receiving Bravecto for the first time in June 2015, she gradually began losing vision in both her eyes. The condition was not recognized as possibly being connected to Bravecto, and she received a second dose of Bravecto in September. She is now almost completely blind, and it was only after I warned my sister in law about Bravecto that she connected the blindness to Bravecto. Fortunately the warning came in time to stop their three dogs from receiving a third dose. As it is by now well known that the effects of Bravecto can be delayed for even longer than a year, I am hoping that the two Jack Russell Terriers will remain healthy and with no adverse reactions to fluralaner.
    I am just thankful that I had decided to do some research after my FORMER vet tried to convince me to give this drug to my puppy, who was only 8 weeks old at the time. I refused to let her be subjected to a drug that I knew nothing about and told her I would reconsider and let her know when I take my pup for her 2nd vaccination. During research I typed in “Bravecto” in the Facebook search field, and found both the group “Does Bravecto Kill Dogs?” & “Does Nexgard kill dogs”. Needless to say, I have decided to fire my vet and NOT use Bravecto for my pup. My decision to change vets may seem a bit harsh to most people, but the reason was not that she tried to sell me the drug, but the manner in which she actually tried to bulldoze me into buying it, even though she knew that my pup doesn’t get into contact with ticks and doesn’t have a flea problem…

  • Jeni Tolzmann

    Jen, you did a great job on this article! It is simply stated and gets the point out. I too, can attest to nexgard. We lost Gretchen, our Mini Dachshund, a few months after giving it to her. On the coattails, of Does Bravecto Kill Dogs, I started Does Nexgard Kill Dogs. Knowing what I know now, I can’t help but think if my VET was more educated and open minded to Gretchen’s symptoms, perhaps she would still be here. Vets are recommending these drugs and insisting they are the best – without doing their own research. Gretchen had ALL the side effects that are noted on the side of the box and STILL he dismissed the notion of having anything to do with nexgard ( I can’t give the drug the respect of capitalizing the first letter). VETS need to be more educated and stop taking the word of a ” sales-rep”….a sales rep…Really??

    • poorlady

      So sorry for the loss of your dog Jeni. My Joey has been on Nexgard during the flea season last year and this and I noticed no side effects except a bit of itching but not excessively. I will certainly be trying Spinosad instead. He’s a 17 month old Cocker Spaniel and he means the world to me and our old Golden Retriever gal Lily.

  • Grid

    My dog had a massive reaction to Bravecto – he had vomiting and diarrhoea. Simply the 12week effectiveness may seem appealing but you have to wonder what is it that actually stays in the system for that long. We decided to stick with Comfortis (Spinosad) which we have had no adverse reactions at all.

  • Freshh20

    This past 2 weeks have been very conflicted. We chose NexGard in place of our usual summer treatment for fleas and ticks. Our Shih Tzu developed a heart murmur one week after taking the first dose of NexGard. He had a physical prior to Tx and our Vet did not notice a mumur (9 years old), ever! He also developed a corneal ulcer at the same time. Very disturbing. The corneal ulcer could have been from something other than toxicity in the blood, but who will ever know.