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Home > General > Does Cornstarch Kill Fleas? Vet-Reviewed Facts & FAQ

Does Cornstarch Kill Fleas? Vet-Reviewed Facts & FAQ

Cornstarch on a table

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Reviewed & Fact-Checked By

Dr. Chyrle Bonk

Veterinarian, DVM

The information is current and up-to-date in accordance with the latest veterinarian research.

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Fleas are one of the more annoying aspects of pet ownership—they are also no picnic for our pets and can carry diseases. While many flea medications are available on the market today and are the best option for getting rid of fleas, some people opt for natural and home remedies to prevent and kill fleas.

One such home remedy people often mention is cornstarch, but is this effective in killing fleas? Unfortunately, no evidence exists showing cornstarch’s effectiveness in killing fleas. Read on below to find out more.


Why Cornstarch Is Ineffective in Killing Fleas

Some believe the powdery substance of cornstarch traps and suffocates fleas, but this is rarely true. The only way cornstarch may be remotely effective is by sprinkling an ample amount on small areas in your home where you see fleas and vacuuming them up. The cornstarch may help suffocate the fleas when used this way, but this method may be messy and not as effective as other treatments.

As far as applying cornstarch directly onto your pet, this will not effectively kill fleas and will just create a mess on your pet’s coat.

Cornstarch in an Ingredient Bowl
Image Credit: Michelle Lee Photography, Shutterstock

What Do I Do If I See Fleas?


For starters, the best method for avoiding fleas is to prevent them in the first place, but if your pet is outside often or in contact with other animals, odds are they’ll be exposed to fleas. Fleas can enter your yard through wildlife and domestic animals, which is inevitable. However, if you’re prepared, they shouldn’t be too hard to get rid of.

Contact Your Veterinarian

Keeping your pet on monthly flea and tick prevention is the best method of preventing a flea infestation. Your veterinarian can prescribe a safe and effective flea medication that will kill any fleas that bite your pet—this will also help prevent infestations. Be sure to avoid over-the-counter medications as some can be ineffective and even unsafe.

close up fleas on cat
Image Credit: KanphotoSS, Shutterstock

Use a Flea Comb

If you see fleas on your pet, you can remove them using a flea comb. Fleas are tiny, and they are excellent jumpers. Using a flea comb is effective in trapping these little pests and their eggs in the comb and removing them from your pet’s coat.

Give Your Pet a Bath

Commercial flea shampoo can have harsh ingredients for your pet, such as pesticides. Instead, you can make your own flea shampoo as a safer and more natural option.

Here is a recipe to make a safe and effective flea shampoo:
  • 1 cup apple cider vinegar
  • 1 cup unscented, dye-free liquid dish soap
  • 1 cup filtered water

Combine ingredients and pour the mixture into a bottle that allows you to dispense a little each time you bathe your pet. Leave the suds on for 5 minutes in order to suffocate the fleas, and rinse.

If you don’t have time to make homemade flea shampoo, you can use Dawn dish soap but don’t use it too often, as this can dry out your pet’s coat.

To find out about other safe and effective flea shampoos, talk to your vet.

gray and white ragdoll cat taking a bath
Image Credit: eeechos, Shutterstock

What Types of Flea Medications Are Available?

Flea medications come in various forms: topical applications, flea collars, oral medications, sprays, powders, and of course, flea shampoos. Your veterinarian is the best source for choosing a safe and effective flea medication.



It may be tempting to grab something in your cupboard to kill fleas, such as cornstarch, but there is no real evidential backing that these home remedies are effective in killing fleas.

Fleas are not only a nuisance but can be dangerous, as they can carry diseases. So, the CDC recommends keeping a sanitized home by regularly washing pet bedding and rugs and vacuuming. Keep your pet on veterinary-recommended flea preventative, and if you find an infestation in your home, contact your veterinarian and local experts to determine the safest way to stop the complex life cycle of fleas.

Featured Image Credit: Michelle Lee Photography, Shutterstock

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