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Seresto vs Dewel: Which Flea & Tick Collar Is Better?

Nicole Cosgrove Profile Picture

By Nicole Cosgrove

seresto vs dewel

Review Summary

For many pet owners, using a flea and tick collar is much easier and more cost-effective than administering a dosage of pesticide every month. Collars are set-and-forget solutions that can stop problems before they start, making them great solutions for outdoor pets.

Two of the most popular options are made by Seresto and Dewel, so if you’re in the market for a new collar, chances are that you’ll come across both. However, that doesn’t mean they’re equally effective.

Seresto uses two proven pesticides that are absorbed through the dog’s skin, whereas Dewel is full of essential oils that are supposed to discourage parasites.

Dewel is definitely the better choice if you’re on a budget or squeamish about applying chemicals to your pet’s body, but other than that, Seresto has it beat handily across the board.

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A Sneak Peek at the Winner: Seresto

Rating Image Product Details
Best Overall
Seresto Seresto
  • Easy-to-use
  • Repels and kills ticks
  • Water-resistant formula
  • Runner up
    Second place
    Dewel Dewel
  • One size fits all
  • Fairly inexpensive
  • Not likely to harm your pet
  • What Are the Differences Between Them?

    Looking at the differences between Seresto and Dewel isn’t just about comparing two different collars; it’s ultimately about comparing two totally different pest-control philosophies.

    Method of Application

    Both are collars that your dog wears around their neck, but that’s about as far as the similarities go.

    Seresto comes in two different sizes, one for larger dogs and another for smaller. Dewel is one-size-fits-all, so you just tighten it to your dog’s neck and trim off any excess.

    They both work in a similar fashion. As your dog wears the collar, the active ingredients begin to wear off on the skin, where they are absorbed into the bloodstream. Then, once a flea or tick bites your dog, they get a dose of the formula, causing them to fall off or die.

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    What Are Their Active Ingredients?

    Seresto uses Imidacloprid and Flumethrin, two insecticides that have been proven to kill fleas and ticks. Imidacloprid is a nerve agent that paralyzes fleas, causing them to eventually starve to death, whereas Flumethrin repels and murders four different kinds of ticks.

    Dewel collars are primarily soaked in lemon eucalyptus, with a bit of citronella oil, linaloe oil, and lavender oil thrown in for good measure. The idea is that these scents overwhelm and disorient fleas and ticks, causing them to fall off.

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    Which Kills Fleas Better?

    There’s really no comparison here. Seresto is leaps and bounds better when it comes to killing fleas, and in fact, Dewel doesn’t claim to kill them at all.

    The idea behind natural treatments like essential oils is that they’re “good enough” without dousing your dog with potentially problematic chemicals. This also makes them gentler on the environment.

    Is the trade-off worth it? That’s not something that we can answer for you. All we can say is, if your primary concern is eliminating fleas, Seresto is the clear, indisputable choice.

    Which Repels Fleas Better?

    Seresto kills fleas on contact, so in that sense, it “repels” them. They can still jump on your dog, however — they just won’t live to regret it.

    Dewel is designed to be more of a repellent than an insecticide, so you’d think it would win this category handily. However, we feel that you’re much more likely to deal with new fleas with a Seresto collar than you would with a Dewel model.

    What Kills Ticks Better?

    Again, only Seresto kills ticks. Dewel is designed to confuse them, forcing them to fall off your dog — and it’s questionable whether it even does that.

    However, you should know that even Seresto will struggle to eliminate ticks that are already on your dog. That’s because the tick killer on the collar targets younger ticks, so fully-grown adults may be unaffected. As a result, you may have to check your dog thoroughly to eliminate any existing parasites before putting the collar on.

    Which Repels Ticks Better?

    We think Seresto is much better at repelling ticks than Dewel.

    One of the active ingredients in Seresto, Flumethrin, kills juvenile ticks and tick eggs on contact, so they never have the opportunity to latch onto your pup. This prevents any new outbreaks.

    Dewel, on the other hand, supposedly overwhelms ticks with its strong, natural scent. We’re sure that ticks don’t like it, but given the choice between a bad odor and starving to death, many ticks seem to be able to cope with the smell just fine.

    Which Is Safer?

    This is one of the more controversial questions. Studies have shown that Seresto is completely safe for dogs, but some owners feel that putting a toxic nerve agent on their dog’s skin is just a bad idea in general.

    Dewel, on the other hand, is completely safe (although some dogs may experience skin irritation).  However, there’s a decent chance that it’s completely safe for fleas and ticks too, which may compromise its safety for pets.

    Seresto is significantly safer in at least one respect. It’s designed to break away if it gets snagged on something, so you don’t have to worry about your dog getting stuck or injuring their neck accidentally.

    Which Is Cheaper?

    Dewel is significantly cheaper than Seresto, as you might expect. Then again, it’s less effective too, so the savings might not be worth it.

    Which Lasts Longer?

    Both collars have been designed to protect your dog for up to eight months, but you should monitor your pet toward the end of that timeframe, as their effectiveness can wane over time.

    While both are waterproof, their effectiveness can also be diminished if your dog spends a great deal of time in the water.

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    Quick Rundown of Seresto:

    Seresto Flea and Tick Collar for Dogs 1

    While it’s an over-the-counter flea and tick solution, Seresto is one of the few that uses proven insecticides to remove parasites.

    • Kills fleas and ticks in all life stages
    • Collar will break off if snagged
    • Eliminates bugs on contact
    • On the pricier side
    • Some users may not like putting harsh chemicals on their dog

    Quick Rundown of Dewel:

    Dewel Pet Dog Collar

    Dewel is also an over-the-counter solution, except it relies on essential oils to deter insects rather than strong pesticides.

    • Not likely to harm your pet
    • Fairly inexpensive
    • One size fits all
    • Limited effectiveness
    • Doesn’t kill pests
    • Extremely strong odor

    What the Users Say

    Products like flea collars are so ubiquitous that you’ll find a staggering amount of information on them from user feedback. We scoured the internet to find what people were saying about these two products to give you a better idea of how they really work.

    Since both of these collars are available without a prescription, there was a ton of information available to us — and most of it confirmed what we already wrote.

    Users were attracted to the Dewel collar because they were suspicious of chemicals and insecticides, and they liked the idea of protecting their pets with natural ingredients. There were few reports of allergic reactions or other health issues from the Dewel collars, but many people found the smell off-putting.

    However, many people found that they did little to stop fleas and ticks from hopping on their dogs, nor did they reduce existing populations. They were also surprised to find that the collars didn’t actually kill fleas, which meant that the ones it repelled often ended up in their carpet.

    Those who bit the bullet and attached a Seresto collar generally had better experiences overall. They often saw greatly reduced flea and tick populations, although the reduction wasn’t as much as you’d see from a topical or oral treatment.

    There were more reports of side effects from the Seresto collar, but that’s to be expected, given that it uses medication instead of natural ingredients. It’s important to monitor your pet’s health once you start them on any kind of flea treatment, and this collar is no different.

    Many users were concerned about the safety of petting their dogs while wearing the Seresto collar, especially if they had children. There have been no reports of issues from people petting dogs with Seresto collars, but we understand the concern. If that’s true for you, you might want to switch to a different treatment.

    The effectiveness of the collar varied somewhat by breed as well. Dogs with thicker coats, like huskies or Malamutes, often saw reduced effectiveness, as the chemicals couldn’t reach their skin. If you own one of these dogs, you’ll either need to find a way to situate the collar right on their skin or choose another option.

    Unless your dog develops issues related to the Seresto collar or you have strong objections to the use of pesticides, we can’t see any reason not to choose it over the Dewel, and the experiences of other users we read about only serve to cement this opinion.

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    Both the Seresto and Dewel collars are easy to buy and use, making them extremely convenient as flea treatments go. They’re also long-lasting, so you don’t have to worry about your dog being unprotected if you forget to give them their treatment one month.

    Beyond that, though, the two products have little in common. The Dewel uses natural repellents, which makes it popular among users who are opposed to the use of chemicals on dogs but also greatly limits its effectiveness.

    The Seresto collar, on the other hand, is extremely effective, but it should be, as it’s coated in powerful insecticides. Ultimately, it’s up to each individual owner to decide whether it’s more important to keep their dog’s body free of parasites or pesticides.

    Featured Image Credit: Luisella Planeta Leoni from Pixabay

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