Does Borax Kill Fleas on Dogs?

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Most dog owners know that having fleas around is a serious problem.

Not only are these parasitic bugs a nuisance for you and your pet, but they can also be dangerous if left unchecked.

Luckily, there are easy, natural ways to get rid of fleas and protect your dog from future infestations.

One of the most popular methods is using Borax to kill fleas on dogs.

But how does it work?

Does Borax kill fleas on dogs?

Does it just repel them?

Does it kill flea eggs and larvae?

And how effective is it?

Read on to find out everything you need to know about using Borax for flea control on dogs.

Does Borax Kill Fleas on Dogs?

Borax is a naturally-occurring mineral made up of sodium, boron, and oxygen.

It’s been used for centuries as a disinfectant, cleaning agent, and insecticide.

In the past few years, it’s become a popular natural flea treatment for dogs as it does not contain any chemical ingredients. 

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It has been used for hundreds of years as both an insecticide and pesticide because of its effectiveness at killing insects without harming humans or animals (or even plants). 

Does it Just Repel Them? 

According to the Pesticide Research Institute[1], Borax will not just repel fleas.

It will kill them on contact by dehydrating them and causing their exoskeleton to dry out.

Fleas also hate the taste of Borax, so they stay away from it, keeping them from your pet.

Does it Kill Flea Eggs and Larvae? 

Yes, Borax will also kill flea eggs and larvae.

This is important because it will help to break their life cycle and prevent future infestations.

Related: Do Dogs Get Fleas in the Winter?

How Effective is it?

Borax is a very effective natural flea treatment for dogs.

According to the Journal of the American Veterinary Medical Association[2], it’s safe to use, kills fleas on contact, and also helps to prevent future infestations by killing flea eggs and larvae. 

It also has several different uses. Borax is used in making laundry detergents, which means it’s great at removing grime and other dirt.

Additionally, it has natural insecticidal properties, which makes it a popular choice for people looking to remove fleas from their homes and clothes.

Is Borax Safe for Dogs?

Is Borax Safe for Dogs?

The short answer is “yes.” Borax is safe for use on dogs.

This means that if you’re looking for a cheap, natural way to get rid of those pesky little vermin on your dog’s fur, borax might just be the solution you’ve been searching for. 

Is Borax Safe for Puppies?

According to the U.S. Food And Drug Administration, borax can be toxic to dogs if ingested in significant quantities.

It should never be used on puppies because their bodies are not developed enough to handle it.

However, Borax can be very effective in killing fleas on dogs and does not typically cause any side effects when used properly for small infestations on adult dogs.

Is Borax Harmful to Dogs?

No, borax is not harmful to dogs if used as directed.

It’s a natural mineral that’s been used for centuries and is safe in moderation. However, if your dog ingests large quantities of borax, it can be harmful. 

Only use it on small areas of your dog’s fur and avoid contact with their eyes, nose, and mouth.

If you’re concerned about your dog’s safety, always consult with a veterinarian before using any new flea treatment.

Does Borax Kill Fleas on Dogs?

How to Use Borax for Fleas on Dogs

Now that you know all about using Borax, it’s time to learn how to do it. Here’s a step-by-step guide on using Borax to kill fleas on your dog.

  1. Vacuum your house thoroughly, paying special attention to areas where your dog likes to spend time. This will help to remove any flea eggs or larvae that are already present in your home.
  2. Make a paste by mixing equal parts of Borax powder and water. 
  3. Apply the paste to your dog’s fur, using a flea comb to work it down to the skin. 
  4. Leave it for at least 12 hours, then shampoo your dog to remove it.
  5. Vacuum your house again to remove any remaining flea eggs or larvae.

Repeat this process once a week for three weeks to break the flea life cycle and prevent future infestations.

Diatomaceous Earth Vs. Borax for Fleas

Diatomaceous earth (DE) is another popular natural flea treatment. It works by dehydrating and killing fleas on contact.

However, it can be harmful to dogs if inhaled, so it’s important to use it carefully.

According to the Pesticide Research Institute[3], borax is a safer option because it’s not dangerous if inhaled, and it’s just as effective at killing fleas.

Safe Borax Alternatives for Dogs

If you’re looking for a safe alternative to Borax, there are a few options.

You can try diatomaceous earth, salt, or boric acid. You can also make a flea trap by putting some dish soap in a bowl of water and placing it near where your dog spends most of its time.

Final Thoughts

Fleas can be a real problem for you and your dog. They can live in your home, on your clothing, or even on your carpet.

These pests can make their way into the house without you even knowing it. And while there are many ways to get rid of fleas, not all of them are as effective as Borax.

Borax is a natural mineral that’s been used for centuries to kill fleas.

And while it’s safe to use on dogs, it’s vital to avoid their eyes, nose, and mouth. You should also rinse your dog off after 12 hours to prevent any irritation.

If you’re looking for a safe and effective way to kill fleas, Borax is a great option. Just make sure to use it carefully and follow the instructions.


Here are a few other common questions people ask.

How Long Does it Take for Borax to Kill Fleas?

Borax starts killing fleas on contact, but it can take up to 12 hours for it to be fully effective.

How Long Does it Take for Borax and Salt to Kill Fleas?

According to a research article on HomeSteady[4], both borax and salt will kill fleas on contact. However, it may take up to 12 hours for the borax to be fully effective, and the salt may not be as effective if it’s not left on for at least 30 minutes.

Can I Put Borax on My Dog?

Yes, you can put borax on your dog. Just make sure to avoid their eyes, nose, and mouth, and rinse it off after 12 hours.

Can You Use Borax on A Mattress to Kill Fleas?

Yes, borax can be used on a mattress to kill fleas. Just sprinkle it on the mattress and leave it for 12 hours before vacuuming it up.



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