PetMeds® Frontline Plus Questions

Some of the more common recent questions I’ve received in the clinic regarding f and its use for flea and tick prevention in pets. A big concern I often receive is the quality of Frontline Plus being carried by online pharmacies like 1800petmeds and whether it is the same as those used and sold by veterinary offices. The truth of the matter is that Frontline Plus is a prepackaged product by Merial, and is the exact same one carried by 1-800-PetMeds as your local veterinarian. Improper application is one of the most common reasons for flea treatment failure

Another common question is, “Why does my pet still have fleas after applying Frontline?” (after a few consecutive months. The most common reasons for flea treatments failing is typically because of improper application, or more commonly failure to treat the environment of the pet, including the home and yard; where 80% of the flea life cycle occurs. Along the same line, some products, however will work better on some pets than others. So, if there are still fleas even after properly treating the home and using Frontline Plus for several months, I would suggest having your house professionally treated by an exterminator and/or change to a different product such as Advantage.

If a pet still has fleas, many veterinarians will use the product more frequently than once monthly, sometimes as often as once every 2-3 weeks. However, this process is often considered to be “off label use,” and I would not use the product this way unless first speaking with your pet’s veterinarian. If a client is currently using a different topical such as Revolution or Advantage, it is safe to change to Frontline Plus after 3-4 weeks from the date of last application of the other product. While Frontline Plus is labeled as waterproof, I usually advise clients to wait at least 24 to 48 hours before bathing their pet. Side effects to Frontline Plus are rare but may include hair loss/skin irritation at site of application, (rarely) digestive upset, (and even rarer) immunological reactions of the blood or neurological reactions like seizures. Again, these are very rare, as most pets tolerate this product quite well.

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  1. Hi I use Advantage on my golden retriever only when I need to but it seems in Coronado, CA the fleas have become resistant to most everything. My boy has cancer so I will not use a systemic tabs such as Comfortis and have also tried natural repellant sprays from Mercola. Our house is clean but he must be picking up a few fleas on walks as when I brush him every day I occasionally see one or two. I know they die when they bite him from the Advantage, as I see a dead one on his white covered dog bed now and then but the flea bites make him crazy. His skin looks wonderful, no visible bites or red marks, he gets bathed every two weeks with an enzymatic shampoo. Everything is spotless and clean but I believe he may now have a psychological itching. He doesn’t scratch in front of me but when I return home from being gone he has pulled out hair everywhere. When we talk walks and he meets another person or dog he immediately sits down and scratches outrageously. He has been on prednisone oral for awhile which helped but I hate giving it to him with his cancer. I have heard about Apoquel but have never tried it. Any suggestions? Is there such a think as psychological itching? Or could occasional flea bites make him itch constantly. He is almost 10 years old and I also wondered if this might be a senior oddity. Thanks so much sorry for the long post.

    • Dr. Michael Dym, VMD veterinarianJanuary 25, 2015 at 3:42 pm · Reply

      Flea bites and/or other type allergies, including environmental inhalent/contact allergies known as atopy may be involved. I DOUBT problem is psychological. Low dose pred may be best choice to control itching or mild combination product like temaril p which has VERY low dose pred in it, as well as antihistamine. Unfortunately apoquel is NOT to be used in patient with cancer

  2. Thanks so much Dr. Dym, I did not know about the contraindications with Apoquel and cancer as I had not researched the drug yet. Yes it was Temaril P he was on before that worked well for his itching, although the first few weeks of loading doses made him really tired and depressed seeming. I guess that looks like my next step though, I have ruled pretty much else out, maybe I can wean him down eventually to one tab of Temaril P every other day after all the loading doses and a month or so on one tab daily. I appreciate your input very much.

  3. I used Sentry PurrScriptions for cats 5 lbs. and over on my adult cat that weights about 20 lbs a week ago and saw no results. Is it okay to use Advantage II for large cats within about a week of using the Sentry?

    • Dr. Michael Dym, VMD veterinarianMarch 18, 2015 at 1:33 pm · Reply

      Should be able to use advantage here without a problem, even if sentry just applied.

  4. I just bathed my dog and noticed he just got fleas. Can I use frontline plus right away? Or do I have to wait? I saw a vet on YouTube say if you bathed your dog wait 48 hours before applying frontline plus. Please help me: ( I know after I apply frontline plus to wait 48 hours before bathing. But if I just bathed him and he’s dry can I apply now or wait 48 hours. Please respond fast. Thank u

    • Dr. Michael Dym, VMD veterinarianMarch 18, 2015 at 1:03 pm · Reply

      Usually must wait 48 hours to apply front line after a bath. Other option I prefer here is the oral pill comfortis which I think is much more effective.

  5. I just bathed my dog and noticed he just got fleas. Can I use frontline plus right away? Or do I have to wait? I saw a vet on YouTube say if you bathed your dog wait 48 hours before applying frontline plus. Please help me: (

  6. My puppy is 37 pounds (and growing) and I just realized I have the frontline plus for 45-88 pounds. Is it ok to give to her or should I just give her half of the large dosage? (Looks like the ounces in the 23-44 pound are exactly half)

  7. My puppy is 37 pounds and I have the frontline plus for 45-88 pounds. Is it ok to give to her or should I just give her half of the large dosage? (Looks like the ounces in the 23-44 pound are exactly half)

  8. My black cat has fleas – she’s an indoor cat and only ventures out for a few minutes every so often to chew on grass. We aren’t sure how she got fleas, but she got them, possibly from sitting in the windows because our neighbor’s yard is like a jungle and we live in row houses, so the yards are connected. We bathed her with apple cider vinegar and cat shampoo, combed her, dried her, and applied Ultraguard Pro. Not sure it did the trick, and since the house is full of fleas and we are trying to manage it, we’ve quarantined her to the bathroom. I’d like to be sure that she is safe to come out and roam so that the fleas go after her and die. Is it safe to apply Advantage II after one week? I have two small children who have tons of bites right now – we are having a hard time controlling this. Thanks, in advance!

  9. Do you love your pet? Then don’t use Frontline, Advantage, or Advantix!
    Topical flea, tick, and de-worming products such as Frontline and Advntix are toxic and can cause pets to have mild to extremely adverse effects. Many products have different active ingredients, but they all work in similiar and harmful ways. They are toxic.
    Unfortunateely, we were one of the life-threatening cases after applying this stuff.
    Our German Shepherd had an adverse reaction FOUR times to different brands of what is basically the same thing. The first time she became so lethargic she didn’t eat or drink much for a few months. She slept ALL the time and didn’t even bark when the doorbell rang (she ALWAYS barks!) Took her to the vet 3 different times and said they couldn’t find anything wrong other than dehydration. I asked about a correlation with this product and they said NO WAY!
    Applied the product a 2nd time 6 months later, and noticed the same odd behavior and unsteadiness. The vet again said it couldn’t be the topical we gave her and thought she was depressed from being lonely.
    Gave her the 3rd dose about 6 months later because she was scratching so much. I thought she had fleas and the vet insisted it was safe. Within three hours, my dog had no control over her hind legs and was panicking and shaking uncontrollably. I will never forget the fear in her eyes. Took her to the emergency room. By the time we arrived, she i could walk but was not herself. The vet did thorough blood work and found nothing. I showed him the box of Frontline I applied and said over and over again I thought it was the cause of these problems, but he insisted it wasn’t possible. He said the side effects included on the box was preventative and it would take such an extremely high dose to have any kind of reaction it wasn’t really possible.
    A month later, we found our dog on the floor convulsing, foaming at the mouth, and completely paralyzed. She couldn’t breathe and we thought we were watching her die. It was horrifying to witness. We calmed her down enough to stop the convulsing and took her to the emergency room again. They admitted her into ICU for a week! Tested and x-rayed her for possible meningitis or spinal tumor, but still found nothing wrong.
    Took her to a new vet who also insisted it couldn’t be the topical, but my gut still knew otherwise. She gave us a different brand to use because it had different active ingredients and insisted it would be fine. I never used it, though, for fear of another adverse reaction.
    A year later, which is now, our dog had her fourth topical treatment. We found several ticks, worms in her stool, and she was scratching a lot. I got out the Advantage Multi our vet sold us and insisted was safe, even for our dog who had severe reactions with Frontline in the past, and applied it. Six hours later, we found her on the carpet seizuring. She was unable to move and had no control over her bowls. I knew it was the Advantage Multi I put on her. This could not be a coincidence FOUR times!
    Called the Advantage Emergency Hotline and she said they’d never heard of a reaction before and she couldn’t tell me how to get this stuff off or what to do. She was only interested in the lot number on the Advantage box! I told her she should Google what this product is doing to people’s pets. There are thousands of pet owners online complaining of these same adverse reactions to these flea and tick products.
    We got our dog in the tub right away and shampooed as much of this out as we could (I know now to use Blue Dawn Liquid Dish Soap instead of shampoo because it’s a better de-greaser to get this waterproof product off. These products start absorbing into the skin immediately, so time is of the essence. Once the Advantage Multi was removed, our dog became noticeably better.
    Time will only tell if she will have residual complications from this as she has in the past.
    No one should be applying these toxic flea, tick, and worm prevention products to their pets. They can cause neurological damage, renal failure, skin disease, and even death. They are pesticides that are not safe for animal or human contact and need to be investigated.

  10. I have a 35 pound begal but accidentally bought – pound frontline. Is it ok to still use it on her?

  11. I have a 35 pound begal but accidentally bought 45 – 88 pound frontline. Is it ok to still use it on her?

  12. I would not use the front line labelled for a dog on a cat.

  13. Isn’t small doses of frontline plus for 5-22lb dogs a bit of a weight difference? I always fret when it is time to dose, though I buy product for big dogs and use syringe. We have 7 dogs of all weights. I had a dog that had a seizure from this. A mild one, but scared me. This year in Missouri the fleas came out and we had a hard time getting under contro, we just never had problems before this yearl. Finally Advantage spray, after trying a couple natural ones, gave dogs relief. Treating carpets and such also is a must. Our only worry in past years were ticks, but this year fleas were maddening. Time to apply FL plus again and fretting about using Advantage and FL together. Really would love advice on this please. If I have to choose one it would be the Spray cause fleas abandon ship when they get this sprayed on the dogs. Have to do once a week or so but dogs were suffering so badly.

    • I would use EITHER advantage or Front line. I dont use both. If either of these not working for you, you can consider trying oral comfortis and/or nexguard, which is also effective. I do recommend treating home and usually have it professionally exterminated if problem very bad

  14. I was reading some of comments about dangers. I have always worried about this, but nothing “natural’ worked after spending a small fortune.The clove spray worked while wet on dogs but next day, wham, that gets expensive spaying it everyday. Treating surroundings is a must but only goes so far. When pets are suffering and getting sores from digging you just can’t experiment with this and that till you solve the problem. I had to break down and take a chance. Now sores and fleas are under control. I have experienced the dangers of chemicals on pets as a siezure a few years back, Once and only once and now choose not to let them be miserable, but you need to be smart about it and research the best products available first. If fleas got maddening for me just watching dogs dig into themselves, imagine what they are going through. I am conservative with dosage and then ask questions if I have them.

  15. This is kind of an unusual situation in that i have a medical condition (chronic pancreatitis–11years now, which leaves me unable to do much at all). I saw my male cat, Pilar (14 years old) scratching himself horrifically, and literally tearing out his fur. Now he has fur, but only in on the top of his head com on the top of his upper body. The hair beneath his ears is virtually gone, and where there is “no hair” on the rest of his body, it’s just wisps of thin, white hair. His stomach has no more hair and is pink skin.
    I saw NO fleas–anywhere, and started wondering if this was a senility issue. Finally I saw a giant flea crawling across where he still has a good coat of (white) hair: on his neck.
    I immediately, which is something I rarely do, do to the pain i experience, went to PetSmart and bought Frontline, came back home and applied it. I didn’t do it right, so against my own knowledge, and in complete fear i re-applied it, correctly, the next day, and he was listless. It seemed to work. (P.S. Pilar is a surely INDOOR cat, and I never leave the house–except for emergencies, so I’m still perplexed as to how this all started). He slept all day, but he’s not drinking his water, and the fleas that seemed to die/disappear after that second dose seemed taken care of. I understand that environment maintenance is crucial, but I don’t have a working vacuum, and even if I did, it’s such a large place it would take me many times of rest to complete the vacuuming process. Instead I ordered Raid flea control and sprayed it (as described on the bottle) in His two usual lounging-spots, and also just everywhere. For about 3 days it looked like all was well.

    Now, for the first time, I’ve found 3 fleas (lively, easily escaped) on ME, and other than lying around, Lar is simply in a state of terror: constantly shaking his head frantically, responding rapidly to a bite, ripping out hair again…etc. the look in his eyes is one of confused terror, and for the last 7 years that I stopped being able to function, he’s been my only pal. Needless to say, I have had him since he was a baby, and this is all I can think about. He deserves better. I’m scared and utterly sad, and he’s terrified.
    What should I do? I’m afraid to go to c vet because they’ll just saw the obvious. I’m unable myself to do the things required: foggers, vacuuming etc, and even if I COULD, I REFUSE to issue him a THIRD dose of Frontline in just 3weeks. I don’t want Lar to die. He’s so old. Is there a company that does these things for people who are medically incapable? I’m right in refusing to give him yet another dose of Frontline in only 3 weeks, right? Any suggestions? I’d like to say thank you, so much, in advance for any answer(s) or info you might have for me. P.S. I live in Portland, OR.

    • Sounds like you need to look at another flea product such as oral comfortis from 1800petmeds, which will require a script from a local veterinarian. Also sounds like your kitty needs a thorough physical exam and medical evaluation, as well as to see if any prescription meds might help with patient comfort. Given your health situation, I would suggest trying to find a local house call veterinarian in your area

  16. When dosing my golden retriever who is very hyper, he moved and I missed and some of the frontline got on his fur. I am not sure what got down to the skin. Can I give him a second dose? He is about 80 pounds.

    • HI Gina. I would not dose again, as we arent sure he did not get enough actually applied. I would wait at least 2 weeks, before which you can reapply the product if needed at that time

  17. Hi my I have a 70 lb pitbull! I bought flea medicine for 88lbs or higher, can I use it or should I try and take it back?

  18. I have two indoor cats that recently got fleas. Eleven days ago I bathed both of them with a flea shampoo. I was able to get it all off of one of my cats but the other, who has front claws, tore me up so bad I just had to try to remove the remaining shampoo with a wet towel which still didn’t get it all off. The following day when she was dry but crunchy she vomited several times. I continued to wipe her down but could still see the fleas. So two days ago my neighbor gave me a dose of Revolution per cat and I used it on them. I have vacummed several times, made a mixture of baking soda and salt let it sit on the carpet and vacumned that up. Its been three days since I used the Revolution topical on the cats and the fleas seem to be dying off slowly. I am using a flea comb to get rid of them faster but they are both still itchy. Tonight I poured Borax underneath my couches and scrubbed it in to control the environment without having to use a fogger and I will vacuum it up in the morning. Meanwhile, the cats are still itchy and losing hair everyday. Have I used too much on them or should I use the Frontline that I purchased. I just feel like its too soon to put another topical on them. I don’t have much money but can’t take it anymore! HELP!!!!!

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