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. Almee – you can give Frontline/Advantage every 3 weeks (I am not a vet but my own vet has told me this). Capstar (one pill good for 24 hours) will kill every flea on her while you are waiting for the spot treatment to settle into the skin. Capstar is from your vet or petmeds also. Hope this helps.

  2. Hi Caroline. Thank you. I just have her another real good combing, sprayed her beds house again and applied frontline.
    She scarfed down a nice dinner and several cookies and is napping comfortably. Thank you!

  3. Sure Almee. Before my dog got cancer I used spot treatments every three weeks in conjunction with Capstar if I saw a flea on her in between times and after every bath (you must wait 24 hours after bath (to completely dry) before applying spot treatments. The capstar kept him free of fleas for the day before I could reapply the Frontline. Next time you get your Frontline make sure you get some Capstar for times like this. Make sure you vacuum every day now for the next week as well as washing bedding daily until you break that cycle and the larvae and eggs are all gone as well. Good luck!

  4. You’re a good person Caroline. Thank you for all the tips and for caring! Best to you….

  5. Dr. Michael Dym, VMD veterinarianAugust 28, 2014 at 6:21 pm

    Fine to use the advantix a bit earlier, but I would consider alternative flea/tick product such as trifexis, comfortis, or topical revolution. Also remember you may need to treat home as well with good product like flea busters which you can find on line. Much of flea life cycle occurs in home

  6. can frontline plus for cats 8 weeks and older be used on a dog that weighs approx. 15 lbs. and is 13 months old?

  7. Dr. Michael Dym, VMD veterinarianAugust 31, 2014 at 7:58 pm

    I dont use topical front line products off label. I use the products as packaged and labelled

  8. Hi,
    We have an indoor car with fleas, we gave him frontline about a week ago and a bath with flea shampoo last night. He still had fleas, when is the soonest I can give him another dose of frontline?

  9. Dr. Michael Dym, VMD veterinarianSeptember 26, 2014 at 9:37 pm

    Usually I would wait at least 2 weeks between front line doses. However if situation severe, consider also dosing with oral comfortis, which I think will work better for you

  10. Hi,we found fleas on my 5 yr old 10lb dog a week ago, We bathed him and applied frontline plus. I vacuumed washed and sprayed everything for the past week. We gave him a capgaurd pill (same as capstar) 3 days after appling frontline and then I gave him a flea shampoo bath 3 days after that (still seen live fleas on him). I have vacuumed the entire house everyday and emptied canister from vac outside. Only see fleas on the dog. I treated the yard the day after I found fleas on him. Today is 1 wk 2 days and I found 2 live fleas on the dog. Help:( called frontline and they assured me that the product is working and I can use another spot on treatment with the frontline. They said double dose don’t hurt the pet it’s just a waste of product. It’s been 9 days should I still see fleas???

  11. Dr. Michael Dym, VMD veterinarianOctober 13, 2014 at 3:39 pm

    You likely have problem in the dog’s environment so important to have house and/or yard treated professionally. Also consider oral comfortis from 1800petmeds, which I have had much greater success with in recent years over front line

  12. Hi, I used Sentry flea medication on my cat last Sunday because the pet store was out of frontline plus. I went back yesterday and bought some frontline plus. Is it okay to apply it to her today after its only been a week with the sentry?

  13. Erica, I am not a vet but I think it is too soon to apply the Frontline. Call your vet and ask as I am not familiar with Sentry. However, cats are highly sensitive to topical flea medications and frequently can have reactions. If it were my cat I wouldn’t risk it so call your vet and ask as soon as possible 🙂

  14. Dr. Michael Dym, VMD veterinarianOctober 26, 2014 at 8:22 pm

    I would wait one more week before applying

  15. Hello. Thank you for your help. Our two indoor/outdoor cats have a flea issue. We have fogged our home quite thoroughly, washed the cats bedding, our bedding,vacuumed the house completely. Sprayed our furniture. We have never seen any in the home, only on the cats. We have treated them with Frontline plus every 3 weeks for the past 3 cycles and they still have fleas. We can only expose ourselves to chemicals so many times.. (Meaning, i dont want to to keep fogging…)… Any suggestions? . Thank you

  16. Dr. Michael Dym, VMD veterinarianNovember 19, 2014 at 5:14 pm

    Try oral comfortis from 1800petmeds which has been approved for cats for flea control and prevention.

  17. I have a 20 lb dog. Is it ok to give the 23 to 44 lb. dose. The store was out of the smaller dosage.

  18. Is it ok to give frontline 23-44 lb dose to a 20 lb dog?

  19. 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.

  20. Dr. Michael Dym, VMD veterinarianJanuary 25, 2015 at 3:42 pm

    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

  21. Dr. Michael Dym, VMD veterinarianJanuary 25, 2015 at 3:47 pm

    I dont think it should be a problem, as long as no history of allergic reactions.

  22. 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.

  23. 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?

  24. 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

  25. 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: (

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