The Best Flea Treatment for Cats

Wipe out an infestation fast

The 30-Second Review

The best flea treatment for cats should kill the fleas in your cat’s fur without causing harmful side effects. To help us uncover what products were safe and effective, we consulted with pet and insect experts, researched active ingredients, and tested the finalists ourselves. In the end, the right choice for you is a matter of your cat’s needs and personal convenience.

Best Monthly Flea and Tick Treatment

Frontline Plus for Cats kills all states of fleas, plus ticks and chewing lice. Its long, sturdy applicator makes it easy to apply directly to the base of your cat's neck.

Sentry Fiproguard Plus for Cats uses the same active ingredients for half the price, but the applicator is messier — not ideal when handling insecticides.

Fast-Acting Flea Relief

Oral medications kill adult fleas fast, but they don’t stop new fleas from growing or kill any other pests. Our top picks are identical — they come in a tiny tablet and start working in 30 minutes.

The Best Flea Treatment for Cats

Our favorite spot-ons are Frontline Plus for Cats and Sentry Fiproguard Plus. Both products use the same insecticide/insect growth regulator combination to kill all stages of fleas, ticks, and chewing lice. Like all spot-on treatments, the medicine is applied to a small area at the base of your cat’s neck, so they can’t lick it off. Because they’re spot-ons, you will have to keep your cat away from children and other pets for 24 hours until the product dries, but they start killing fleas in 12.

Sentry is the cheaper of the two, but we preferred Frontline’s clear, snap-off applicator. When we opened Sentry’s applicator, some of the medication leaked out — we had to take extra caution to make sure it didn’t leave a residue on our hands and scissors.

If you cat needs relief from fleas as quickly as possible, we recommend the oral tablet Sentry Capguard. All three of the oral flea medications we tested — Sentry, PetArmor, and Capstar — were identical products, but Sentry was the cheapest, with PetArmor coming in a close second.

They all start working in 30 minutes and kill 90 percent of fleas within six hours. The downside of oral flea medication is that they only treat existing fleas — they don’t prevent fleas or treat other insects. But because the medication comes in a tablet, you don’t have to worry about coming into contact with the product.

Our Picks for the Best Flea Treatment for Cats

Best Overall

Frontline Plus Apply this liquid medication to your cat's neck once a month to kill all stages of fleas, ticks, and chewing lice.

Frontline Plus for Cats gets our pick as one of the two best spot-ons when it comes to killing pests. It kills all stages of fleas — eggs, larvae, pupae, and adults — as well as all stages and ticks and helps eliminate chewing lice.

Its formula is safe enough to use on kittens as young as 8 weeks old as long as they’re over 1.5 lbs, in addition to breeding, breastfeeding cats. Kittens are just as susceptible to fleas and ticks – but can’t always handle the insecticides used in other topical medications. So it’s a win all around.

Application was easy too; all you have to do is point the applicator between your cat’s shoulders and squeeze. After application, you should keep children and other pets away from your cat for at least 24 hours to allow the product to dry.

All spot-ons work similarly, but Frontline’s long, snap-off applicator tip made it easier to apply. By comparison, Sentry Fiproguard Plus and PetArmor Plus require scissors, and some of the liquid leaked out.

Another Option for Long-Haired Cats We like Catego’s long, space-age applicator tip, ideal for long-haired cats. It was the easiest to apply, but it cost twice as much as Frontline and can’t be used on pregnant, nursing, elderly, or disabled cats.

This EPA-approved product uses a fipronil and (s)-methoprene combination as its insecticide/insect growth regulator combination, so it kills fleas and prevents them. Frontline starts killing fleas within four hours after application and kills 100% of fleas within 12, making it the fastest-acting spot-on in our top picks.

Each application kills and prevents fleas and ticks for a month and prevents fleas for almost twice as long — up to six weeks. Because spot-on medications are waterproof and absorb into the skin after 48 hours, they’re good options for cats that like the outdoors, and you don’t have to reapply after your furry friend gets wet.

In terms of price, Frontline is one of the more expensive spot-ons we tested at $32 for 3 applications.

From right to left: Frontline Plus, Catego, Sentry Fiproguard Plus, PetArmor Plus

A Cheaper Spot-On Medication

Sentry Fiproguard Plus It uses the same active ingredients as Frontline Plus, but was a little messier to apply. The upside: It's half the price and smells faintly like lemons, not chemicals.

Sentry Fiproguard Plus is another good option. Like Frontline, this product kills all stages of fleas, some ticks, and helps eliminate chewing lice. It’s identical in packaging and label claims to PetArmor Plus, but it’s half the price.

While the formulas are similar, but we uncovered a few differences during our hands-on testing. Specifically, we found that we preferred Frontline’s clear packaging and snap-off tip. By comparisons, Sentry had to be cut open, and the medicine leaked out onto our scissors each time. You’ll have to take extra caution to make sure it doesn’t leave a chemical residue on you or anything you touch.

We noticed a range of scents too. Most spot-ons (Frontline Plus included) have a distinct chemical scent. That’s to be expected – these are chemicals after all – but Sentry’s was slightly more mild, even faintly citrus. But really, the difference is tiny, and the scent from any medicine will likely fade after a day or so.

Each application takes 12 hours to begin killing fleas and 48 hours to begin killing ticks. After application, you should allow the product to dry for 24 hours before letting your cat around other pets or children.

Sentry Fiproguard Plus was the cheapest spot-on in our top picks at $12 for three applications.

Best Oral Treatment

Sentry Capguard All three of our tablet picks use the same insecticide and come in a tiny tablet, but Sentry was the cheapest.

If you just need to treat your cat fast, Sentry Capguard, PetArmor FastCaps, and Capstar, and are all decent options. Each brand includes six tiny tablets that use nitenpyram to start killing fleas within 30 minutes. Plus, all the flea-fighting takes place internally, so you don’t have to worry about coming into contact with the insecticide.

Since these tablet don’t help prevent future generations of fleas, they’re best used as an immediate, temporary solution. You’ll give your cat a tablet up to once per day until the fleas are gone. But if you’re dealing with a true infestation (you’ll notice fleas on your furniture and carpeting), consider switching to a spot-on after the first day or talk to your vet about prescription options.

You can use these tablets with kittens as young as four weeks old and on cats weighing anywhere between 2 and 25 lbs. Each of the labels also say these products are safe for dogs and puppies, so they’re a versatile option if you have multiple pets.

All three of these oral flea medications were identical in look, smell, and packaging. The only differences between them were brand name and price, and for that reason, we recommend Sentry Capguard at $15 for 6 tablets. PetArmor FastCaps came in a close second at $16 and Capstar was the most expensive at $27.

Did You Know?

Fleas are more common in cats.

The Banfield Pet Hospital State of Pet Health 2016 Report says that fleas are almost twice as prevalent in cats than they are in dogs, making flea education an important topic for cat owners. Even if your cat stays indoors, they should still be treated for fleas. The report states, “Indoor-only pets are also at risk for fleas and ticks since these parasites can unknowingly be on people, other animals, or materials that enter the pet’s environment.”

In the United States, Washington, Oregon, Florida, Louisiana, and Alabama are the top five states for flea problems. Fleas are most common in the South and on the West Coast because they thrive in hot, wet environments.

For best results, talk to your vet.

Oral tablets can be more convenient — they can’t be washed off (or licked off) of your cat. But the oral medications we looked at only treat an existing flea problem and could be difficult for pet owners to get their cats to swallow.

Dr. Ari Zabell at Banfield Pet Hospital explained there are currently no over-the-counter oral options available for both flea treatment and prevention — the oral medications that do exist require a prescription. Topically applied medication comes in over-the-counter and prescription options too.

“Some of the current OTC medications are simply medications that were previously available only by prescription, but have since proven safe enough to be available over the counter. Prescription medications often use newer ingredients to which fleas haven’t yet developed resistance.”

While insecticide-resistance in fleas is a growing concern, some vets are skeptical. In an article from Veterinary Practice News, Dr. Michael Dryden, DVM, Ph.D. suggested that when a flea medicine doesn’t seem to work, it’s likely due to user error. “I have investigated homes that by owner description sound like there could be a resistance problem but found, when I looked closer, there was always a reason for the failure. None was ever resistance.”

To leave no room for error, read the medicine’s directions before you apply it, set reminders for when it’s time to reapply, and regularly wash your cat’s bedding and vacuum your floors.

Always take precautions when dealing with new medications.

All pets are different and can react to medications in different ways. Some cats can be sensitive to the topical medications being placed on their skin, but the same can go for oral medications too.

If your cat has allergies or other ailments that could affect how they handle a new flea medicine, consult your vet first to determine the best medication for your cat.

If you haven’t noticed an improvement in your cat’s fleas after a few weeks or if your cat experiences any side effects, contact your vet for guidance.

The Best Flea Medicines for Cats: Summed-Up

Flea Medicine for Cats
The Best
Frontline Plus for Cats
Spot-On Treatment
Sentry Fiproguard Plus for Cats
Runner-Up for Spot-On Medication
Sentry Capguard
Oral Treatment
Capstar Flea Treatment Tablets
Runner-Up for Oral Treatment
PetArmor FastCaps
Runner-Up for Oral Treatment