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. Would I be able to give him the rest of the dose today?

  2. HI Rachael. I usually dont suggest redosing the front line, even at lower dose, for at least 2 weeks after the initial dose. In future, it may be best to consider an oral prescription medication for fleas if you need additional coverage; i.e such as oral comfortis, etc from 1800petmeds.

  3. I applyed my nine-month-old cat frontline plus The day after Christmas and he hasn’t been the same since he eats and drinks but all he wanted to do was sleep he hasn’t played in probably four days now what is going on?

  4. Hi Gina and thank you for your question. If you haven’t already, we recommend you consult your veterinarian. However, for non-emergency questions, you can contact Dr. Dym directly using our Ask the Vet form. I hope your kitten is feeling better soon!
    ~ Abby, PetMeds Pro

  5. I need help… I’ve done everything I treat my cats with Frontline plus and they’re still coming back from being outside covered in ticks nymphs, all around their eyes and ears where there’s not a lot of hair. I take tweezers every single night and pick as many as I can off them and eyes are swollen they look uncomfortable and they really don’t like me picking them with tweezers every night, I’m sure it hurts what else can I do these ticks are going to kill us literally my husband and I both have Lyme disease which we had gotten in The Last 5 Years when we moved out to Mount Desert Island and I have never seen anything like this in my life they literally are everywhere all the time

  6. Hi Stephanie. I’m so sorry you’re having trouble with ticks; this can be a difficult problem and usually requires a multi-prong approach including treating your yard and home. We do always recommend you discuss this with your veterinarian. However, for non-emergency questions, you can contact Dr. Dym directly using our Ask the Vet form. We hope you’re able to resolve the situation quickly!
    ~ Abby, PetMeds Pro

  7. I applied my dogs monthly dose while it was a little dark and she moved when I put it on.. I noticed that the applicator was pretty dry so im guessing its possible I had a bad dose and there was no medicine in this applicator.. Im afraid to put another dose on her but I dont smell it on her and I dont see the “wet fur” after.. I would like to put another dose on but worried that either she got a little bit or none and I hate to take her up north when i am not to sure anything got on her.. Can I do another dose?

  8. Hi Nicole! For any medical concerns, we always recommend you consult your veterinarian. However, for non-emergency questions, you can contact Dr. Dym directly using our Ask the Vet form.
    ~ Abby, PetMeds Pro

  9. I put flea and tick solution on my cat,i didn’t realize I did it 24 days ago,i did it 6 days early,will this harm my cat

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