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.

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