What Kills Fleas On Dogs Instantly?
Here's how to get rid of fleas fast.
Fleas can infest your pup (especially if your dog isn’t taking a reliable flea preventative), but they don’t have to stick around for long.
If you notice your dog has a flea infestation, you’re not here to play any games — it’s time to get rid of those pesky fleas … fast.
We spoke to Dr. Dwight Alleyne, a veterinarian working with betterpet, Dr. Sara Ochoa, a veterinary consultant with DogLab, and Dr. Michelle Burch, a veterinarian at Paramount Pet Health, to figure out what kills fleas on dogs instantly — or almost instantly.
How quickly can you kill fleas?
How fast you can kill fleas will depend on the product you use.
“There are products that can kill fleas as quickly as 30 minutes,” Dr. Alleyne told The Dodo. “Topical products, such as flea shampoos, can kill fleas almost on contact.”
Over-the-counter flea medication
There are plenty of over-the-counter (OTC) flea treatment options that you can find either at your local store or online. These products typically range in how fast they start to kill fleas, from 30 minutes to a full 24 hours.
“Some OTC options for killing fleas include topical products such as Frontline and Advantix,” Dr. Alleyne said.
Try Frontline Plus from Amazon for $38.99 (starts working in 24 hours)
Try K9 Advantix from Chewy for $29.98 (starts working in 12 hours)
In addition to Frontline and Advantix, which can also prevent new flea infestations, both Dr. Burch and Dr. Ochoa recommended Capstar because of how quickly it begins working.
“Capstar is a pill that you can get at your local pet store that will start killing fleas in as little as 30 minutes and stay working for 24 hours,” Dr. Ochoa told The Dodo. Keep in mind, though, that Captsar won’t prevent new flea infestations, so you’ll need to pair it with a preventative medication, like the OTC options above or the prescription medications below.
Get Capstar from Amazon for $36.99
Prescription flea medication
The fastest options for killing fleas with prescription medication are Comfortis or Trifexis, which also work as effective preventative medications. “Both products contain the active ingredient spinosad, which will begin killing fleas within 30 minutes of ingesting the tablet,” Dr. Burch told The Dodo. “Both Comfortis and Trifexis last for 30 days.”
Comfortis has the active ingredient of spinosad to kill and prevent fleas. Trifexis, on the other hand, contains both spinosad and milbemycin for flea, heartworm and intestinal parasite prevention.
Get Comfortis from Chewy for $114.39
Get Trifexis from Chewy for $125.49
Natural options
When it comes to non-chemical options, like plant-based products with essential oils, these aren’t recommended by veterinarians because there are more effective options out there.
“At this time, there are not any natural options that I recommend for fast and efficient death or control of fleas,” Dr. Burch said.
You can, however, reduce the amount of fleas on your pet with a bath. “This will quickly remove the fleas that are currently on your dog,” Dr. Ochoa said. (You can even use a natural flea shampoo, like this one from Vet’s Best, to help.)
Keep in mind, though, that your pet will need to be on an effective flea prevention medication to prevent fleas from coming back.
What kills fleas on dogs instantly?
“To eliminate fleas on your pet the quickest, I recommend giving a dog Capstar every 48 hours for three doses,” Dr. Burch said. “On the first day Capstar is administered, [also] give a monthly flea preventative, such as NexGard or Simparica.”
Get NexGard from Chewy for $68.99
Get Simparica from Chewy for $57.97
While fleas are a pesky nuisance you’ll want to get rid of fast, giving your dog a routine flea preventative will make sure she never gets infested to begin with.
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