Seresto collar not working? Find out why and what to do!

Fleas are the worst! They cause too much pain and suffering. When left untreated, the infestation can lead to multiple dangerous problems as well. Thankfully, there are quite a few treatments that work effectively, and the Seresto collar is one of them.

The Seresto collar is an extremely popular flea-prevention and flea-removal treatment that many dog and cat owners prefer. However, sometimes, it fails to work, and panic prevails. What must you do now? To get the answer, you should know how the collar works and the reasons why it may not be working. Let’s dig deeper to extract all these answers.

How does Seresto collar work?

Seresto collarThe Seresto collar is an 8-month treatment that starts working within 24 hours. It kills flea larvae and adults through contact. It does not wait for your pet to be bitten. This is one of the things we like best about the collar. It also works to prevent a new infestation. The preventive treatment begins after 48 hours. 

Since it has active ingredients, it works continuously and slowly to get rid of an existing infestation. It also works on ticks, but you must remember that ticks that are already on your pets will not die immediately after they wear the collar. So, you should get rid of the live ticks before putting the collar on. Within 48 hours, it will start preventing new infestation. So ticks that try to infest after this will be identified and killed in less than 6 hours. 

Another point to note is that if there were pupae on the pets when they wore the collar, fleas or ticks will emerge from them for another 6 weeks. The control is slow but effective. Expecting instant results is, however, wrong.

Do Seresto collars work?

Indeed, they do. They are extremely effective in preventing new infestation and removing existing problems for 8 months. The action does not wear off with time. 

The collar is safe for dogs and cats over the age of 7 weeks, but if your pet is pregnant, old, debilitated, or nursing, we request you to speak to your vet before starting the treatment.

Seresto collar not working – what to do?

dog with seresto collarWe have come across quite a few cases in which the Seresto collar has not worked or been effective. There are a few reasons why this may happen. Let’s explore them:

  1. Your pet gets baths or swims very often: Even though the collar is water-resistant, frequent baths will reduce its effectiveness. The sellers do not recommend baths more than once a month. We would also like to advise against taking your pet swimming during the course of this treatment.
  2. Your pet has a very thick coat: It is hard for the collar’s medication to penetrate a thick coat, and thus, it may not work.
  3. Your pet already has ticks: As we explained clearly earlier, if there are live ticks attached to your pet, please remove them before putting the collar on. Ticks that are already attached will stay there for weeks even if your pet is wearing the collar. 
  4. Your pet is not wearing it: Please understand that the Seresto collar works only when your pet is wearing it. Upon removal, the action will stop immediately. So, make sure the collar is on all the time, even when swimming or bathing. This also applies if the collar tears. 
  5. Your pet just started wearing it: Tick and flea removal takes time. As aforementioned, the action kicks in 24-48 hours from the time your pet started wearing it. Also, the process is slow and can take weeks. Please be patient.

If the collar still doesn’t work, it is probably faulty or fake, and we request you to speak to the seller for clarification. 

We hope our article helped you and answered all your questions. For more information or if you have any doubts, please let us know through comments.

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  1. Hi! I have a cat allergic to flea bites that has done well with seresto in he past2 years. I changed it recently 2 months ago and it is not keeping them off now. I bought it from a vet. The tail is the worst. Not a lot of fleas seen but a few and enough that I have had to put him on prednisilone for the awful scabs and itching. HELP! Should I remove it and put on a new one? thanks, Della

  2. My dog wear the belt since two week but still tick is there and its not even reduced. Infact its increase ticks pls let me know what do i do ,

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