Best Flea Meds

Cat scratching itself
(Image credit: mage by Uschi Dugulin from Pixabay)

As a pet parent, there’s nothing worse than seeing your fur baby scratching and biting all day long. Fleas and other parasites can make your pet’s life miserable, but thankfully there are some great products on the market that get to work fast and offer long-lasting protection. Our favorites are safe, effective, and start working immediately, so your four-legged friends will have that smile back on their dial before you know it.

Top pick for dogs

Flea medicine

(Image credit: Amazon)

Seresto Flea and Tick Collar for Dogs

Sustained release technology for eight months of protection

Providing a whopping eight months of flea and tick prevention, this vet-recommended collar delivers outstanding protection. Unlike a lot of other collars on the market that only kill fleas when they bite, this version from Seresto works by killing fleas and ticks the minute they land on your dog. Non-greasy and odorless, the collar gets to work killing and repelling fleas within 24 hours of application. Easy to apply and using sustained-release technology that offers continuous protection for the full eight-month period, this collar gets a gold star for providing long-lasting and affordable flea and tick prevention for your canine companion.

Top pick for cats

Flea medicine

(Image credit: Amazon)

Advantage II 6-Dose Large Cat Flea Prevention

Kills fleas before they bite

This easy-to-apply and pre-measured topical flea treatment comes in ready-to-use tubes for a mess-free application. Waterproof after 24 hours, this treatment kills fleas through contact, so your kitty doesn’t have to get bitten for them to die. It starts to work within 12 hours of applying it and offers 30 days of continuous protection. Advantage II kills fleas at all stages of life, from eggs to adults, and the fragrance-free formula means your feline friend won’t even know they have it on.

For extra-large dogs

Flea medicine

(Image credit: Amazon)

K9 Advantix II Flea, Tick and Mosquito Prevention

Provides waterproof protection for 30 days

If you’ve got a big fur baby on your hands, then this specially designed formula for dogs over 55 pounds is a winner. Killing fleas, ticks, and mosquitoes on contact, each pack provides four monthly doses that come in easy-to-apply pre-measured applicators. Getting to work within 12 hours and protecting your dog for 30 days, the formula is also great for treating dogs with current flea or tick infestations. Once applied, the active ingredients get to work by slowly spreading over your dog’s skin, killing all pests they come into contact with. Waterproof after 24 hours, it’s a great choice if you have a dog that loves spending time in the water.

Best cat oral treatment

Flea medicine

(Image credit: Amazon)

Capstar Fast-Acting Oral Flea Treatment

One tablet kills 90% of fleas in six hours

If your feline friend is feeling miserable thanks to a current flea infestation, then this is the treatment you want. Getting to work killing fleas within 30 minutes of being administered, Capstar tablets provide fast-acting relief from these pesky parasites. Killing 90% of fleas and their eggs within six hours, you can safely administer one tablet a day until the infestation is resolved. Each pack contains six oral doses, so there’s no messing around with topical treatments, and you get all the convenience of a tablet without having to worry about getting a prescription from your cat’s vet.

Best dog oral treatment

Flea medicine

(Image credit: Amazon)

Advantus Soft Chew

Medicine disguised as a tasty treat

Unlike hard tablets, these soft savory chews taste more like a treat than a flea treatment. Suitable for dogs and puppies over 10 weeks of age, one chew starts killing fleas within an hour. Available in two strengths depending on your dog’s size, these convenient chews are safe to give once per day and are suitable for dogs with animal protein allergies. Containing imidacloprid, the same active ingredient used in Advantage II, these tasty chews hit fleas hard in a formula your fur kid will love.

Best for dogs & cats

Flea medicine

(Image credit: Amazon)

Adams Plus Flea and Tick Shampoo

Keep all your furkid’s flea-free

If you have a mixed-pet household and want a treatment that can be used on both dogs and cats, then this shampoo is a great option. Containing an insect growth regulator, it kills fleas, ticks, lice, and their eggs and larvae, and prevents any further development for up to 28 days. This sensitive skin formula is great for pets with allergies, containing aloe vera, lanolin, coconut extract, and oatmeal to soothe skin, and will keep your furkid’s coat looking shiny and feeling soft. It's safe for use on kittens and puppies over the age of 12 weeks and has a pleasant and fresh scent.

How to choose the best flea medication

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Keep a smile on your furry friend’s dial by making sure they stay flea-free all year round. Our top pick for dogs is the Seresto Flea and Tick Collar, with its sustained release technology that offers protection for eight months. For the feline pet parents out there, our favorite product is the Advantage II 6-Dose Large Cat Flea Prevention, which gets to work after just 12 hours and lasts for 30 days.

When it comes to oral treatments for current infestations, Capstar takes out the trophy for cats, with one tablet killing 90% of fleas within six hours. And for dogs, Advantus Soft Chew gets our vote every time for delivering a potent dose of medication in a soft and tasty treat.


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