Bayer Seresto Flea & Tick Collar, Large Dog – Review

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Ticks & Fleas Driving Your Dog Crazy? Does the Bayer Seresto Flea & Tick Collar for Large Dogs work?

It’s that time of year again…summer at last! It seems winter would never end here in the U.P. of Michigan yet again. The only problem with warm weather is all the bugs and creepy crawlies it brings along with it…especially for dogs. Ticks and fleas can cause quite a lot of misery for us all once they get a foothold.

There’s a lot of options to keep these critters at bay…sprays, drops, shampoos, and collars. I’ve used them all at one time or another on our dogs in the past and one that I find pretty easy and effective to use is the flea and tick collars.

So, I thought I’d look into one of the popular pest control collars at Amazon to see what a lot of other dog owners are using and found this one by Bayer to be well known and used by many…here’s some of the good and the bad things that I found digging through the reviews there from people who have bought it and used it on their dogs.

Bayer Seresto Flea & Tick Collars Review

Product: Bayer Seresto Flea and Tick Collar, Large Dog
Where to Buy: Amazon
Seller: Petco
List Price: $84.99
Price: $69.99
Sale: $59.99
Average Amazon Rating: 4 out of 5 stars
Country: Germany
Size: Large


  • Lasts up to 8 months
  • Veterinarian recommended
  • Non-greasy
  • Odorless
  • Water resistant
  • Available in three sizes- Large dog, Small dog, and cat
  • Release mechanism for additional pet safety
  • Attachable reflectors


  • Dog may be allergic- skin became red and irritated
  • Slow working at first compared to other collarsBayer-Seresto Flea Tick Collar large dog
  • Reports of some dogs becoming ill with vomiting and/or diarrhea after using
  • A few complaints of dog’s hair turning gray under collar

**NOTE –This product is for dogs and puppies 7 weeks of age and up and above 18 pounds!

Please read all instructions on the label or any that may arrive with the packaging!

My Thoughts on the Bayer Seresto Flea & Tick Collar?

Well, I’ve used similar flea and tick collars on our dogs in the past with no problems so far, but have yet to try this collar myself…of course, yes, on my dogs…not me! I’d look kinda silly…

Seeing that there are always some good points and some bad for products like these collars, I’d at least give the Bayer flea & tick collar a try…I do like the fact that they are odorless and non-greasy! I hate the smell from the other brands of collars we’ve tried…that’s all you can smell all summer…ugh!

Plus, the fact that there is a built-in emergency release device is another excellent benefit in my book…yeah, I worry too much! I always have the fear that the collar will get caught on something and end up choking one of our dogs to death if it can’t get free…

I guess it all depends on your dog, like people, some are allergic or have bad reactions to certain products, foods, medication, etc. while others don’t, but instead do very well with a particular product.

If you do happen to give this flea & tick collar a try just keep an eye on your dog…same as you would for any other new product right?

Make sure they are still acting “normal” or whatever passes for normal for your dog and look for any signs of illness, skin irritation, lack of appetite, or anything unusual. If your dog has a severe reaction to a new product such as seizures, or continued vomiting/diarrhea I’d get it to your veterinarian right away.

Have you tried the Bayer Seresto Flea & Tick Collar on your dog? What did you think of it? Let me know in the comments below…

I’d love to hear from you! Hope this helps you out and please share it if you like it! ~Sherry 🙂

*Disclaimer – I am not a veterinarian, but a fellow dog owner trying to point out some of the products out there that you may find helpful for your dog…please follow the advice of your veterinarian for your dog and please, again, read the labels!*

10 thoughts on “Bayer Seresto Flea & Tick Collar, Large Dog – Review”

  1. I have 2 small dogs, bought these collars for them, within 2 days they were both vomiting and had severe diarrhea. I am extremely disappointed in the cost of the collars and my dogs reaction to them. Over $100 down the drain because no way am I trying to put them on again. Good god what a mess 🙁

    • Hi Gina,
      Thank you for letting us know about your experience with using these collars on your two small dogs! So sorry to hear your dogs had to go through that…strange how some dogs are fine while others are not and end up vomiting and/or diarrhea. I’m guessing some dogs are more sensitive to certain ingredients used in flea and tick collars.

      I definitely agree and wouldn’t put them on again either if mine had these issues while using them. I’ve recently been looking into using more natural flea and tick repellents, which I’d think would be a safer and healthier alternative to these types of collars. Thank you again for sharing, it’s the main reason why I wrote this…to find out what other dog owner’s experiences are with these collars. I’ll be posting here again soon on an all natural flea and tick repellent I’ve heard good things about…

      Best wishes to you and your two dogs. Do let me know if have any questions or topics you’d like to see here as well. I’d be happy to answer as best I can. 🙂

  2. first time user and have noticed some scratching at collar site and some vomit witch she did at times before collar so I’m giving it a chance to see if scratching stops and vomit is not a constant thing

    • Hi Ron,

      Thanks for stopping by and letting us know what your experience has been with using the Bayer Seresto Flea & Tick Collar on your dog so far. Since it’s the first time using the collar, I’d definitely recommend keeping a close eye on your dog.

      If the scratching continues or worsens I’d recommend removing it, but if your dog is only scratching at it now and then and not too hard to cause skin/coat damage, I’d think it’d be okay to try it for awhile and see how it goes…again I’m not a veterinarian, so please use your own discretion!

      If your dog appears really uncomfortable and has any other issues pop up I’d definitely remove it and have your veterinarian check your dog out.

      It’s hard to say about the vomiting issue though…how long has that been going on before the collar?

      From what I understand, if your dog was vomiting before trying out the collar it must be another issue causing the upset stomach and vomiting. If it’s quite often, your dog may have other health problems that should be checked out since in my experience our dogs rarely have vomiting issues…about the only time they do is in the summer when there’s grass they end up eating for some reason…not sure why dogs do this, but it’s also only on occasion anyways.

      Another thing that might cause temporary vomiting is a change in dog food or type of food your dog is eating…just switching brands suddenly can cause your dog to get pretty sick as we found out many years ago. But, it usually is only temporary, however, that was another visit to our veterinarian that time too…I believe he prescribed a special food for our dog to eat til her tummy got settled down again, if I remember correctly, since it was so long ago.

      Anyways, if your dog is vomiting a lot and appears weak and just not itself, I’d bring it to the veterinarian just to be sure it’s okay to continue using the collar on it. I’m not sure if it’d affect your dog’s health problems to continue or worsen by continuing to use it, but I’d rather be on the safe side.

      I’d love to hear an update on how things go for you and your dog sometime…again, please do what you feel best for your dog, as it seems these collars have been known to cause some rather serious problems for some dogs, but work great for others.

      Thanks again for commenting!
      Best wishes to you and your furry buddy!
      ~ Sherry

  3. Our three year old German shepherd had a seizure one week ago after putting on a seresto flea color so we took the collar off. yesterday he had another seizure and a few hours later he fell over dead in the woods with my husband at his side. I know it was the seresto and have read and heard more tragic stories in the last two days. We loved this dog so much and his life was cut so short by this product. We are very angry and beyond being so sad with our loss. More info needs to be put out about toxicity from this product!!

    • Hello Jacquelyn,
      I am so sorry to hear of your loss of your German shepherd and I certainly don’t blame you for being angry either. I hadn’t been aware of this happening before, although I’ve heard that some dogs have had bad reactions such as vomiting and diarrhea. I’ll definitely look into it some more to see what I can find out about this, since I don’t want to be promoting anything that may have that severe of a reaction. I’m wondering if Seresto has changed their ingredients in some way or if it was a bad batch of them that somehow got out into the market.

      Definitely something to check more into! Thank you for sharing here, and again, I’m so sorry to hear of what happened with your dog…please let me know if there are any other details other owners should be on the look out for in their dog if they’re using this product.

      How long did you have the collar on your dog before he had the first seizure? Did he have any other symptoms or health problems that may have contributed to a problem with the collar? I’m just wondering so we can let others know to avoid using these flea collars if their dog has any of these same health conditions or problems.

      Again, I’m not a veterinarian, just a fellow dog owner, trying to help other dog owners with their dogs, so I’d definitely be very careful about using these…I’m thinking after reading your comment, it’d be safer to try something else! I’ll be doing all I can to find out more info on the recent tragedies you’ve mentioned…and share what I find in another post here asap. I’ll add the link to it in here once I get it done.

      My thoughts and prayers to you and your family. It’s hard to lose our fur babies at any point in their lives, but to lose one at only three-years-old is even harder…definitely something not expected to happen for years to come yet.

  4. My dog and my cat both developed diarrhea after they started using the collars. It could be a coincidence, but I won’t run a second trial on them!

    • Hi S. Alexander,
      Thank you for taking the time to leave a comment. I’m so sorry to hear that both your cat and dog developed diarrhea after they started using the collar. I do hope it cleared up soon afterwards…

      Like you mentioned, it could just be coincidence. Maybe they both got into something they found around the house or outside…or, it very well could be an allergic reaction.
      It’s impossible to tell for sure with only using it once, but I sure don’t blame you for not wanting to risk trying it again…it’s no fun cleaning up the mess!

      Possibly bringing them both to your veterinarian for allergy testing might shed light on the subject, depending on whether or not you want to spend the money to do so, and what your vet thinks about it.

      Or, you could try another brand of collar that may have different results…just make sure to look for one that doesn’t have the same ingredients as the Bayer Seresto Flea & Tick Collars and it states for “dogs & cats” since some may be made specifically for use with either just dogs or just cats, and some might not.

      The collar here, the Bayer Seresto Flea & Tick Collar, is actually only for use on dogs. I wouldn’t use it on your cat again at all.

      Another thing that you could try is Neem Oil, which is used by people on their dogs…not quite sure about cats though, so I’d look into that further before using it on a cat. I wrote about Neem oil quite a long time ago, but if you’d like to read the post, What is the Best Tick Repellent for Dogs? Natural or Chemical?.

      I hope it helps you out and do let me know if you have any questions, concerns, or even if you have other suggestions you found that work for your dog and cat. It’d help me to know more about it and also help anyone else that may be having the same problems as you.

      Thanks again for stopping by! I appreciate the feedback and may you and your furry friends have a beautiful day!
      Best wishes ~Sherry

  5. Hi. I have a doberman. He is 4 months and uses a seresto collar. When I put it on him, he becomes vomiting sometimes and always have diarrhea. He hasn’t had parasites and is with a super premium food.
    So I think the collar is the problem. The veterinary analyzed his diarrhea and the next Monday we will have the results. Perhaps he is infected for any parasite.

    Regards from Spain.

    • Hi Silvia,

      So sorry to hear your little pup is having these problems…I do hope he gets better soon!

      It sounds like he might be having a reaction to the collar if it only happens when he wears it, but I’d definitely do what you’re already planning on doing and take him to the veterinarian.

      It’s hard to say without actually seeing him and how his condition is compared to what he “normally” is…and not knowing how long he has worn the collar, the ingredients of the food, whether it’s affecting his appetite (is he still eating like normal or not interested in eating?), etc.

      Until you know whether or not it is the collar causing his illness, I’d STOP using it for the time being. This way you can observe whether his condition improves, stays the same, or gets worse. Did your vet have any advice on the use of the collar at the time of the initial exam?

      If it gets worse, I’d recommend getting him to the vet immediately or as soon as you possibly can.

      Keep track by writing any symptoms (vomiting/diarrhea) or any unusual behavior down, for each day until you can get him to the veterinarian. Or, if he had no symptoms on some days, I’d be sure to mention that too. It’s much easier to write everything down and bring it with you than try to remember when you’re at the veterinary clinic.

      I’m glad to hear you’ve already had him checked over at your veterinary clinic, and I hope they find a solution for your puppy once the results are in. Following the advice of your veterinarian is what I recommend, but if one vet doesn’t have any suggestions I’d bring your dog to another one for a second opinion if the problems continue.

      I’d love to hear from you again and what your veterinarian found out…it’ll help other dog owners with the same questions too.

      Thanks for stopping by and best wishes to you and your pup!


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