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Anyone else have bad reaction to Frontline?

I put Frontline plus on my dog and she came up in a big weeping sore on the spot I put it.

She has had Frontline plus once before with no reaction. Poor girl is so distressed and trying to scratch it all the time.
I gave it to her a week ago and she was really irritable but only started scratching madly last night and the hair has fallen out and the welt is 3inches round and about 1/2 inch deep.

It’s raw and weeping puss like substance.
I won’t use a product like this again. I’m using powder from the vet and natural remedies to heal it.


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36 Responses to “Anyone else have bad reaction to Frontline?”

  1. megan says:

    I put Frontline for the first time on my cat a year ago. She is a very small cat and sadly since then she is scratching herself all the time. She has to wear a cone around her head almost permanently. Her eyelids and anus get raw and swollen as well. And she is now losing weight. I fear the worse she will get cancer and die from it. Prednisone did not work very well but antibiotic did help.She has to have courses of antibiotic at regular interval to help her immune system to heal her self inflicted wounds. From what I understand the insecticide Fipronil get stored in the oil gland of the animal for a long period. So I try to wash my cat once a week to remove it. For fleas I now use diatomaceus earth which is natural and works really well. I suppose this is what you are using too.
    I think exactly the same reaction happens to cat and dogs I do hope your dog will recover from this permanently. Also I read that some people have got Frontline to pay for all the vet bills relating to this bad reaction.

  2. Tammy says:

    My dog also had a bad reaction. She also has a weeping sore with pus. She is on antibiotics. The main part of the sore is larger than a dollar bill and also extends to the front of her neck. I called frontline to report it. They said they won’t reimburse my vet bills. But they will reimburse what my frontline cost.

  3. Elizabeth M.C. says:

    My dog had previously been on frontline with no reaction. We bought frontline PLUS because the regular brand was not available that day
    My dog began scratching shortly after his first application of frontline PLUS. The scratching coincided with his grooming appointment two days later, and we assumed it was from the grooming.
    The scratching continued for two months so we put him on an allergy formula, grain free diet dog food, thinking it was food related.,
    We have now decided that this reaction might be from the frontline PLUS, and we will no longer apply that starting with his next application.
    I hope that will be the solution to his problem.

  4. both of my dogs had horrible, yet different, reactions to Frontline Plus.

    1. French Bulldog, 5 years old. A week after using it began urinating himself without realizing it while he was sitting or sleeping. I wasn’t sure it was it but there was no other explanation and he hadn’t had that issue prior or since.

    2. Pug, 8 years old. A week after using it had small bloody cuts and welts all around the sides of his face. We took him to the vet and the vet said it was heat stroke and shaved his fur off those areas and told us to put aloe vera on the sores to help them heal. Then we found another spot, on the back of his neck, exactly where we put the frontline. The vet missed it, we shaved his hair off there and found an inch round red/crusty/bloody circle. He’s so itchy he can barely stand it.

    While both reactions were different, I definitely don’t want to try the product again just to “test” out my theory. I will however, never buy/use/recommend Frontline plus again.

  5. Stevie says:

    Our spunky, interactive, talkative 2 1/2 year old indoor cat never had fleas until recently when our dog passed them onto him. We have only had the dog for a year and a half and I have been avoiding using any chemicals on him either because I have multiple chemical sensitivities (MCS). When I started seeing fleas on both of them I finally gave in thinking this was the only option. Now in less than a week our spunky, interactive, talkative cat does nothing but sleep in one spot all day and no longer interacts or talks to us. At this point I am worried and making a call to the vet because for the last few days he didn’t start to remind me about meal time an hour ahead like he always does, and this morning he refused to eat anything. There is nothing else other than Frontline PLUS that could have caused this. We feed him all organic cat food and use Sweatscoop Wheat Litter so this is the first time he has been exposed to chemicals. I wish I would have looked into using diatomaceous earth for fleas before I put these toxic chemicals on our poor cat!

  6. heather murphy says:

    I applied front line to Bobby my shihtzu in Jan2011 shortly afterwards I developed hives and red welts on my body but did not know what it was .Bobby continued to scratch at his ears so I took him to the vet he prescibed a steroid and anti biotic as he said his skin was very pink. After 5 weeks I applied a second dose of frontline within 48 hours I suffered a severe allergic reaction with my eyes and mouth swelling I was rushed to hospital and administered an epipen which has now been prescribed to me as essential by my doctor I am a waiting an appointment with an allergy specialist but since I have never been bothered with allergies before feel that this was caused by frontline just posting this as a warning to others!

  7. Elizabeth says:

    Used Frontline about a week ago and my poor dog is itching, scratching and now chewing his legs all the time. This product should be taken off the market!

  8. Linda says:

    I put Frontline on 6 of my cats. One cat is losing his hair and has a swollen area about 2 inches round with 2 holes oozing yellow pus. I agree this product is dangerous and should be taken off the market.

  9. Brendan Worth says:

    I have a 16yr old staffy bully X who had a bad reaction to Pyriproxifen when I tried it on him recently, then I learnt about diatomaceous earth. ‘Great!’ I thought, and invested in an 11kg bag in order to share it around the community this stuff sounded so good. Unfortunately although it visibly affected the fleas (they dropped off immediately and writhed on the floor) it dried his skin as well. Just treating his bedding for a month did not control the flea population, so I ordered Frontline over the internet. Now he never had a bad reaction to Frontline or Advantage in his youth, but is this frontline PLUS a different formula or is his skin just more fragile and permeable in his old age? He exhibited reaction symptoms similar to the pyriproxyfen and staggered around uncontrollably for an entire day, collapsing with his legs splayed out when he tried to eat from his bowl, and stopped eating dry food completely!
    Various parts of him swelled up, but a few days later he seems to be recovering now. Not what I expected from a product I thought I had tried and proven already :/

  10. Crystal says:

    I also have a Staffy who has had 2 reactions to the drops… once as a pup – itchy for a month, but not to bad. So we haven’t used it on her since. However this year the fleas are HORRIBLE!! I bombed the house, bathed and flea dipped both dogs and cats, constantly spray and vacuum the floors & furniture, new expensive flea collars… but none eliminated the fleas. So I bought the drops… My male Husky did fine, he’s still a little itchy where the fleas were really biting him, but my poor Staffy!! oh the poor girl!! within a few days she developed welts/blotches all over both her sides and inner ears, she is very itchy, and has peed while sleeping 2x!! As long as I make sure and give her 25mg of Benedryl 2x daily she seems ok, but this is ridiculous!!! I will never use the drops of any kind on her!!! We are a week into it and the vet says to just keep up what I’m doing until the blotches are completely gone, but that could be a month!!

  11. Fern Carrasco says:

    My dog has had Frontline several times. This time she started digging at herself, licking and scratching uncontrollably. She has redness and sores all over her belly. She is beside herself, running from one door to another. I read about benadryl use in dogs. Gave her half a tablet and she calmed down. I am convinced the Frontline was to blame. Our Teacup Yorkie had a similar reaction and was put on Advantage. Never again will I use Frontline.

  12. Karinna Dawbin says:

    I too applied Frontline Plus to both my dog and cat. My dog is miserable. He whines constantly and licks and scratches like crazy. He seemed fine before applying this poison to him, poor thing! My cat has sores on his neck where I applied the frontline to him. He too is really miserable and itchy. After speaking to the company, they refused to reimburse me for the product (because I was too naive to save the reciept) and they refuse to do anything else. My children would be heartbroken if this kills their cat. This crap should be taken off the market! Don’t use it!

  13. Sanette. Verster says:

    After 12 years of using frontline on my cat and been twise to the vet for antibiotics she has a sore and a fever but is getting better. A guy at Merial in South africa said she is alergic and just have to use something else. Not nice I wont use that frontline ever again

  14. Joanne says:

    I gave my Min Pin Frontline Plus for the 1st time and she started running around trying to get it off immediately. Then the scratching and biting herself all over. She was also lethargic and panting. I was scared so I gave her 1/2 tab of Claratin and she calmed down a bit. But she feels like she has a fever and is very lethargic now. Taking that stuff back tomorrow and will never give it to her again!

  15. Arlene Whyte says:

    Yes, I too had problems with all of the products for flees and ticks. Ended up that I give Daisy 3-4 Brewers Yeast tablets. She will be 12 years old and has NEVER had either flees or ticks. Tablets get a smiddgeon of peanut butter and anyone who sees her, would think it was filet mignon.

  16. JM says:

    My cat has also had a reaction to the Plus formula… she had tolerated the other formula for years..but the Plus is harmful…a patch of her belly fur fell out–shes chewing her legs and tail constantly and scratches her face, neck and ears as if shes being eaten alive by fleas…she was NOT doing that prior to the application of Frontline Plus. Shes drinking constantly and now shes getting steroid shots to calm her skin down…. and my adult daughter itched as well for 2 days after applying it…Why do these companies take a once trusted product and cause harm?

  17. MS says:

    Never had an issue with fleas… always use K9 Advantix and love it, but store was out, so Used Frontline Plus on my Soft Coated Wheaten Terrier ~ that had a beautiful wheat colored coat… she lost her hair all down her back in big 3 inch spots and it is coming back in brown! She has been scratching for weeks as if she is working a live with fleas and miserable! This should be taken off the market because it is obviously a dangerous product!

  18. Yvonne stock says:

    My 6 year old cat got really sick after using frontline and frontline plus. He would run and roll like crazy after the treatment. He died soon after from kidney cancer. It broke my heart. Poor baby. If I could turn back the hands of time I would have looked for a different solution. He had a big sore on the spot where he got treated. I hate frontline and never again will I use it or recommend it.

  19. Deb says:

    My cat has had a bad reaction from frontline, frothing at the mouth, sezuires, howling. Took emergency vets. They have given him 2 injections, lets hope he gets better poor cat. Never using frontline again.

  20. ford says:

    Frontline contains fipronil. This is a dangerous chemical. Do not get near it if you have a sulfonamide allergy (bactrim). It will kill you. There should be black box warnings on the box! Unfortunately they are using fipronil in and on more products and the residue can be found in our food and in our water. It has a long half life, and it breaks down into chemicals 10 to 30 times stronger than fipronil. It should be banned. It is used in agriculture, on food crops, on seeds, to treat wood against termites and now our pets. Research it and spread the word.

  21. maibui says:

    my cat had a reaction to frontline he has survived the incident at two years old but he cant ever be outside or climb trees or be a normal cat he lost the use of his back legs when he started using frontline now i have him on pet amour i wil never ever go back to using frontline.

  22. Kristin says:

    Oh my gosh! I am scared now, I used Frontline Plus on my cat a week ago and he has always had a beautiful coat. He now has several patches missing around his neck and has a small red sore where the treatment was applied. My smaller female cat seems to have no symptoms. I will be taking him to the Vet tomorrow. If the product has side effects this severe it should not be sold, what is wrong with America? Anything to make a buck.

  23. B. Hutchins says:

    I have been using Frontline Plus for both our Chow and Shih Tzu once a month as a prevention. We do not have a flea or tick problem. Last month when I applied it to the Shih Tzu, he was scratching and jumping around uncontrollably all afternoon and that night. I will never use it again on him. Poor little guy was miserable!!

  24. David says:

    Frontline not a good product. My dog is having a terrible time with it.

  25. tonya says:

    I used frountline flee spray on my nursing cat after being sold it by the vets to use on her and her kittens thta was 3 days ago my cat has now started losing her thick long coat chunks are coming off her tail I don’t kno what to do any advice ?

  26. Julie Gehrt says:

    This product is VERY HARMFUL to cats. We put Frontline on our cat that we had for 3 years. He was foaming at the mouth, screaming and scratching. I gave him not less that THREE baths trying to get this toxic stuff off of him. It still hurt him for almost a week. I though he was gonna die. I WILL NEVER USE THIS PRODUCT AGAIN!!! Anyone thinking about using it, please, I URGE YOU NOT TO! Do not put your pet’s health in jeopardy. There are other SAFER alternatives.

  27. Natalie Leslie says:

    It’s 4am and I just finished giving Oliver (dog) his third bath in 2 days. Poor guy has been trying to scratch his back and rear incessantly since I applied Frontline a few days ago. He wakes me up to scratch his back and can’t get enough. He seems calmer right now. Not sure if it’s from the bath or if he is just exhausted. Used liquid dish soap this time. Going to see if we can both get a few hours of sleep now. Best of luck to all of you and your beloved pets.

  28. Heather says:

    We put Frontline Plus on our 100lb rescue lab. At the vet’s recommendation, we applied it in 2 spots – behind his shoulder blades and near the base of his tail but not where he could easily reach and he has lost most of the fur on his back between the 2 application sites and his skin is red and bleeding. The vet has now given him a steroid shot and he is on antibiotics.

  29. Connie buehman says:

    Used frontline plus on my two cats splitting a single dose, because it just seems like too much medicine. Well it is the worst poison I could have used. The cats started clawing at their necks because I put it on the back of neck just above the shoulder. I did not realize they would be up all night ripping their skin off of their shoulders. This was a horrible sight. I washed them with gentle pet soap and the vet put them on some allergy medicine, And antibiotic for the wounds. Had to put baby socks on their back paws and keep them in cages washed them a few more times. Poor cats, dear God please save other pets from this poison. I found that health food stores have better flea repellent. Do not torture your pets with this poison put it on your on neck and see how that feels.

  30. Jeff says:

    I applied frontline to my 85 lb lab/Vizsla mix and he hates as I apply it and a day or so later he started throwing up and exploding diarrhea. He started itching terribly and has hives. doctor checked for an obstruction but since using Benadryl he is doing better but after the length of Benadryl wears off his hives come back he still doesn’t want to eat or drink. This is BS and it should be removed from the market. All I can do at this point is use the medicines from the vet and pray he makes it through this.

  31. Craig says:

    I had used Frontline exclusively on my dog for years, but at 9 years old she began to lose hair in huge chunks, which would reveal red irritated pus oozing skin. The vet couldn’t figure it out. It seemed almost cyclical, because it happened in October mostly. Then she would recover and be fine. The hair loss gradually got worse each year until at age 11 her entire rear end and tail were completely bald. In desperation, I poured hydrogen peroxide over the entire area each day. This cheap $1 bottle was a miracle. The inflammation stopped and her hair grew back. Fast.

    I am convinced now that the spring and summer applications of the flea protection were causing it. The symptoms would go away when I stopped applying in the winter.

    This is the first season that she hasn’t had terrible dandruff, itchy skin and hair loss in several years. And the only thing I did was stop the Frontline.

  32. Davienne says:

    I just used Frontline Plus on my kitty last week, have used Advantage before with no problems. She is an indoor kitty with no yard access but if a flea comes in one me, it’s immediatley on her and bothering her. I can’t see them on her, she is a Torti/Calico, but the symptoms are there. I believe she is reacting badly due to being agressive, crying, hyper-senitivity along her spine and all around her tail/anus. She is also drinking more water than usual. I comb her fur with a fine tooth comb, it doesn’t scratch her and gets the fine fur out, it’s now full of white flakes & very small dark curved things that don’t move, they weren’t there before, just the white flakes. I have tried to view them with a magnifying glass but too small. I’m irritated with this product, she is miserable, was walking around off and on yesterday crying. Thankfully there are no rashes, no swelling, or other bad spots. Am wondering if I should bathe her and get that stuff off.

  33. Debi Moore says:

    We have used frontline spray on our dogs for many years. This year it didn’t help to control fleas. Vet advised frontline plus. Our rat terrier is 25 yrs old. We used just partial dose on him because of age. within 12 hrs the poor boy was panting and heart racing and has gone progrresively down hill. He wont eat or drink. we have bn giving him Gatorade with a syringe. this helps keep electrolytes in check. We have always taken good care of him and he is a member of our family. If he survives this He will never get flea treatment again. will use homeopathic methods. Vet just gave him steroid shot and a pill that is supposed to help him go pee.

  34. Leslie Shepley says:

    PLEASE DO NOT USE Frontline plus on your pet!!! My 100 lb American Bulldog has had a severe reaction to this product! We have used frontline for several years successfully with no issues. However, this month I applied frontline plus and within a day he had an open wound at the application site that bled and oozed green puss. Additionally, patches of his hair began to fall out excessively. When I noticed this I immediately washed the product off and gave him antibiotics. This seemed to heal the application site wound but now a new wound on one side of the application site has developed with the same symptoms. Furthermore, he is now urinating himself and has not eaten or drank water for two days. TAKE THIS PRODUCT OFF THE MARKET FRONTLINE!!!! SHAME ON YOU!

  35. Pamela Tiger says:

    Oh, dear…I just stumbled on this site after trying to research why our poor kitty has an open, weeping, bloody wound on the back of his neck where I applied the Frontline (and yes, it is Plus) a week or two ago.
    Poor kitty!
    I can’t afford the vet– a checkup is $200!!! Not to mention treatments!
    My son goes to a Tech high school and they have a vet clinic there. Hopefully they can see our kitty in the next day or two. Meanwhile I *was* putting a homemade plantain salve (plantain, olive oil, beeswax) on him, which isn’t helping.
    Starting today, I am now using Triple Antibiotic ointment as per someone upthread.
    We still have fleas…he is and always has been a totally indoor kitty. I have fleas. My son has fleas. I think I brought them from a home care client I have that has outdoor cats 🙁

  36. Frontline products are poison to us and our pets. So are many other flea and tick products. Be careful what you put on your pets. My 6 yr old Aussie got seizures from Frontline Plus. He is on medication to this day because of Frontline Plus. He still gets anxiety attacks too. I got so mad that I have a group of people fighting to get this product off the market. Please join us with your story. Our website is Fill out the form on the contact us page. We need more people to join. Many of the pets of the persons who joined have died because of this poison. Please help us to get this off the market. We have an attorney in New York but just need more people willing to tell their story. You DO NOT need to testify. Thank you.

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