Costco Frontline Plus Review

You’ve probably seen the commercials all over the place for Costco Frontline Plus...

...but have you ever thought it actually might actually be extremely helpful in protecting your furry friends from fleas or ticks?


It contains a few active ingredients such as insect growth regulator and S-methoprene, which can help kill adult fleas within a span of 12 hours, kill ticks and lice within 48 hours, and keep your dog or cat pest-free for up to 3 months.

Tons of household pets are at risk for getting fleas and trying to kill them once they are there is extremely difficult. Regardless of whether you wash your pet constantly or brush them every day and night, these pests will find a way to latch on.

Frontline Plus Review

For Dogs

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Frontline Plus is made to kill ticks and fleas per your dog’s weight.It is very important to make sure that you first pick the right package for your dog’s weight in order to get the correct protection. One of the main ingredients that you’ll find in Frontline Plus is called Fipronil.

It is a broad-spectrum insecticide that disrupts the central nervous system of fleas and ticks.

 Once you apply Frontline Plus to your dog, the Fipronil slowly spreads and helps prevent growth by stopping flea eggs from hatching or larvae from growing. Essentially what it helps to do is disrupt the life cycle that is natural to population of fleas on your dog. Frontline helps to take on 4 of the most prominent ticks in dogs that can carry with them Lyme disease or Rocky Mountain spotted fever. This is all possible by taking advantage of the natural oils in their body.

For Cats

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Frontline Plus for Cats is essentially the same as Frontline Plus for Dogs, though it has a higher concentration of the medicine’s active ingredients.

This is why it is important that you don’t mix and match for different species. Like the one for dogs, this will kill fleas, ticks, and chewing lice at all different stages.

The long snap-off applicator is super easy to apply as well. Same for dogs, you apply the medicine to the base of their neck in a spot where they aren’t able to lick it off, as ingestion could be very dangerous. The best part is, you only have to spread it on once a month for it to work properly.


  • Frontline Plus is very effective when it comes to killing fleas and ticks

  • The application is very simple

  • The brand is top quality and many vets recommend it

  • Begins killing all pests within 12 hours

  • Con's

  • You have to bathe your cat or dog at least 3 days prior or after you apply Frontline
  • The way that it is packaged up is a bit annoying
  • Although it kills ticks on the body, it is not a tick repellent. You will have to make sure your home is tick free.
  • It can be oily and take a while to actually be absorbed under the skin.
  • Can be dangerous if you have younger kids or other pets around
  • There are quite a few reviews of pets experiencing irritation and discomfort after application
  • The Costco Frontline Plus Price can be a bit expensive compared to other flea solutions

  • Competitors

    Vetguard Plus Flea and Tick Treatment for Dogs

    When you look at these two products side by side, you can see that they share a lot of the same qualities. One application lasts a month in both, both are completely waterproof, and both are applied using the same method. The difference is the mixture of active ingredients. Vetguard Plus uses Permethrin and Pyriproxifen, which work in conjunction to do the same thing as the ingredients in Frontline. Many studies have shown that there are not any differences between the ways the two products work.

    Earth Animal Flea and Tick Internal Powder

    The biggest difference between these two products is how you use them. Earth Animal is a powder that works to eliminate fleas through ingestion. The active ingredients in the powder eventually permeate through your cat or dogs. Though this powder is something that will act as a repellent to keep pests away, it’s not supposed to be something that works to bring damage to an already existing problem. One of the biggest issues is trying to get your pet to eat it, as it does not have that great of a taste.

    Vet’s Best Flea and Tick Yard and Kennel Spray

    Again, the biggest difference between Vet’s Best and Frontline is the application process. The Vet’s Best spray is meant to coat the lawn that your pets play on. Fleas live outdoors in bushes, trees, grass, etc. When your pet gets fleas, it is most likely because you have them in your yard. This acts as an excellent preventative measure if your pets are constantly outside. Like Earth Animal, this won’t do your pet much good if they already have fleas.

    How To Use

    First, like stated before, you’ll want to make sure that you have the correct size of Frontline Plus before applying, as it is important to give the right dose for safety purposes.

    Peel back the foil on the package and remove the applicator. Tap on the narrow side to make sure the contents remain in the bigger part of the body before snapping back the top.

    Find an area on your pet that they cannot lick and spread the fur so that the skin is visible. Squeeze everything out onto the skin and voila, you’re done!

    Frequently Asked Questions

    What are some of the major side effects of Fronline Plus?

    Some people say that their dogs have experienced lethargy, vomiting, rashes, and hair loss. This is much more common for those who purchase a package that is for bigger dogs or cats.

    Is this something that you should use year round on your pets?

    Absolutely! Even though it may be colder outside during the winter, it’s typical that your home will be warm enough for fleas and ticks to thrive. It’s best to keep that in mind during any season.

    If my dog weighs more than the highest dosage package, what can I do?

    The highest Frontline Plus dosage will work for dogs up to 132lbs. If your dog weighs more than that, it’s possible to apply multiple doses for small dogs to add up to the correct amount.

    Is there an age limit for Frontline?

    If your pet is any younger than 8 weeks, you will need to find an alternative method to help with their fleas and ticks.