Frontline Not Working?: Information from Frontline Manufacturer

This post has come about because I posted an article about reasons why people might find that Frontline wasn’t working and in that article I basically put any perceived ineffectiveness down to the product perhaps being used incorrectly.  Since posting the article I’ve received comments on the blog and emails from people who have successfully used Frontline for years and who now find that it doesn’t work for them.  They raised the point that if it used to work, but doesn’t now, the product must have become ineffective.

Since I could only gather people’s views on the subject I decided to pass their  concerns on to Merial, the makers of Frontline and ask if they are aware of any issues with Frontline not working.  I don’t have any agenda here, I am just passing on your concerns and reporting back Merial’s reply.

Merial told me that they are aware of speculation on the internet that Frontline  has ceased to be effective. However, their own clinical studies, and those of their competitors, which have been carried out since the product’s launch through to the present, show that Frontline still works as effectively as when introduced.

In the manufacturer’s view, the “myth” of flea products not working is actually the result of three factors:

  • a lack of understanding of who the flea cycle works
  • misconceptions about how flea products work
  • misconceptions about what flea products can achieve.

Merial suggest that if you find that Frontline is not working, you should ask yourself whether you have

  • treated all animals in the home
  • consistently treated them every thirty days
  • treated your home as well as your pet
  • given it enough time; a flea infestation will probably take at least three months to shift.

If you take a break from treatment, even during winter, it is possible for “hitch-hiker” fleas, to survive and lay eggs around your home.  Whilst these might not hatch when the weather is cooler, when summer arrives you will have an infestation in your home without even realising it is developing.  Once you have an infestation, you can’t leave it to treating your pet alone; you need to tackle the flea population living in your house too (remember that only 5% of the fleas live on the pet, the other 95% are secreted around your house).  The eggs and cocoons around your house won’t be affected by you treating your pet; only when these hatch into adult fleas and jump onto your pet will they be killed.  Whilst this will mean that the number of cocoons in the house will gradually diminish, you really need to speed the process up by treating the house to get rid of fleas, which I’ve discussed in earlier posts.  It took me several months to completely eradicate the flea infestation I had; several months of daily vacuum cleaning plus using flea treatments.

Here is a video, recommended by Merial, that discusses the issue of perceived ineffectiveness of Frontline:

Steve Dale: Flea Control

Merial have also sent me an information sheet for pet owners which I may post as a downloadable file.  In the meantime, here are some further information sources passed on by Merial:

UK Customer Helpline (0870 6000 123)

Frontline Webpage

Many thanks to all the people who have commented and emailed; I hope that you have found this post interesting.



20 thoughts on “Frontline Not Working?: Information from Frontline Manufacturer

  1. It seems that Frontline does still work then. It does makes sense that you have to clean your house of the fleas before the dog or cat can be flea free. The advice you gave in earlier posts were invaluable to me when trying to rid the house of fleas. The idea that 95% of fleas DON’T live on the pet but around the house really scares me. . But as you say say you have to be vigilant and it does take time too.Thank you for such clear and invaluable advice, it has really helped.

    • Hi John – it’s a totally gross thought that there are fleas around the house – far more worrying than thinking that they stay on the pet! However, I think that once you realise that, it is a great incentive to really get down to business and literally clean house! It’s a very time consuming business, but if you stick to it, it works.

      Thanks very much for your comment, I am absolutely delighted that you found the advice here useful.

      Best wishes


  2. The idea that 95% of fleas DON’T live on the pet but around the house really scares me. . But as you say say you have to be vigilant and it does take time too.Thank you for such clear and invaluable advice, it has really helped.

  3. This is not true. I have been using front line on my cats for years. It has allways worked great until now. I realize that fleas live for weeks in a cocoon in the carpets and outside. Frontline used to kill any that jumped on my cats. This is not so now. The fleas on my cats are alive and strong just as they were before I treated them.. I believe the fleas have become immuned or the product was over manufactured and now is expired. They do not put an expiration date on the package. Yet, all chemical products expire and lose potency. Frontline is pulling the wool over your eyes. They don’t want to give any body there money back as the pkg says 100% satisfaction guaranteed, that is also a lie.. Thanks for nothing Frontline.-A very expensive waste of money

    • Hi Bonnie – thanks for sharing your experience.

      I know that many other people are saying the same thing, hence my query to Frontline. As I said, I’ve got no agenda – I’ve heard people’s experiences, I’ve put them to Frontline and I’ve reported their answer. I’m not saying who is right or wrong. I can see where dissatisfied customers are coming from and I can see where Frontline are coming from.

      Back to you though; are you treating your house too? If the flea population reaches a certain point (and, as mentioned before, there is an explosion in the flea population this year), your flea treatment (Frontline or otherwise) won’t be able to keep up with killing the adult fleas that hatch and hop onto your cats. Always do the two-pronged approach of pet and home (sorry if I’m preaching to the converted).

      Thanks very much for commenting (and may be pass on your concerns to Frontline on the contact links given in the article).

      • Frontline does not work. It is that simple. I would probably tell you it worked too if I was selling it. It used to work great now it doesn’t. DON’T BUY IT!

    • I too have been using Frontline for years and it is not as effective as it was. I looked to see if the ingredients are the same and they are but it really irritates me. Also, poor people like me can’t afford to have pets anymore. Cat food has gone through the roof. I love my two cats, they are 10 years old and I will keep paying but unfortunately I won’t be able to afford any more.

      • Hi Ellee – sorry to hear your problems with Frontline. You are right that keeping pets is expensive; it’s a shame because having money doesn’t necessarily make you a better pet owner. There are two things I wish people would take into account when they get a pet: love, time and money. Pets take up lots of all three. Often people have plenty of one or two and not the other. We can’t all be wealthy, but we can certainly give our pets the time and love they deserve – I am sure that you do.

        Best wishes to you.

  4. Frontline has always worked for me too, until this year!!!!! I have been vigilant vacuuming, washing, spraying flea killer on my carpets etc. and using frontline. It’s not working! Now I just bought capstar pills, hope they work! Frontline should send me a $160 refund, as I have used their useless product on my cats and dogs for 3 months! Very unsatisfied!

    • Hi Sandy – Capstar will kill off the adult fleas on your animals, but it won’t have an ongoing effect. I’ve used it on my dog to get rid of fleas fast (she gets flea allergy dermatitis) and it’s marvellous, but make sure you treat them with something that offers protection too.

      Sympathise with you on the flea infestation – it does take absolutely months to sort it out – five months isn’t unusual :(

  5. I have always used Frontline Plus on my Golden Retriever, she has never had fleas. As of this year Frontline has NOT been working for ticks. I have always put it on the correct way and my house is very clean. Saturday 11/3/2012 was her appointment with the Vet for yearly check-up & shots. She tested positive for Lyme disease… can this be when she has always been treated every thirty days?? I think the Frontline manufactures must be skimping on a vital ingredient other wise why would a treated dog come down with Lyme disease?? Of course I am VERY upset as I have always done everything right for my beloved dog. This is heartbreaking to say the least. I always bought the Frontline at my veterinarians, but now I will not be buying it again. And I am not the only one. There is something not right with it. I use to speak so highly of it, but not any more.

    • Hi Linda – so sorry to hear your dog has picked up Lyme disease. I can quite understand that you won’t be using Frontline Plus again. What has your vet recommended instead?

      • Thank you! I was told that Vectra is #1, but very lethal to cats and I have one so will not be getting that. I am not sure yet what I will buy.

        • Hi Linda – glad you checked! Ask around at your vets for suggestions, or go on a cat forum website for ideas. Hope you find a solution soon.

  6. Yeah, you know–I know all this and am compliant beyond their recommendations. I’ve been working with cocker spaniel rescue for years with a revolving door of spaniels coming and going from my house over the past 12 years. Some of them coming in with serious infestations. I’ve been using Frontline then Fronline Plus since it came out–10 plus years or something? Anyway–a really long time. In addition to treating all these other areas, fogging every six weeks or so and spraying outside– I manually remove fleas from my guys with a flea comb every to every other night.

    I think there may be a good argument to be made for fipronil resistance in some areas–mine evidently being one of them. This past spring the number of fleas I removed from my dogs at night went from a few to fifty. I don’t think the product is different–but the fleas sure are. I’ve never seen such a thing and am now casting about for alternative measures. It was great while it lasted though.

  7. I’m afraid to say that for the past 10+ years I have used frontline and had no problems until this year, I now have a full infestation and have had to call in experts at great expense to deal with it as my little boy has severe reactions to flea bites. The reason I know it doesn’t work, I caught several fleas on my cat seven days after correctly applying the right dose and put them in a clear sealed container, now frontline claim fleas are killed after contact with the animals skin and fur and will die within 12-24 hours… 72 hours later they are still alive and jumping! This product doesn’t work, this company does rip you off and it’s a disgrace!

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>