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Is Borax Safe for Cats? Safety and Usage Advice

Written by: Christian Adams

Last Updated on January 18, 2024 by Catster Editorial Team


Is Borax Safe for Cats? Safety and Usage Advice

Borax is a multipurpose cleaner that can be used for stopping an infestation of ants or cleaning mold. It’s even become popular as an ingredient for homemade slime recipes! You might also see it being suggested as a “natural” alternative for dealing with a flea infestation. In this article, we’ll look at whether there’s any evidence to suggest that it’s effective at getting rid of fleas, and if so, is it safe to use around your cat?

Before we look at borax in more detail, the short answer is no, borax is not safe to use around your cat. Borax can be fatal to cats, and its use should be avoided if you have pets living in your home.

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What is Borax?

Borax is made from a mineral known as sodium tetraborate decahydrate. It’s sometimes also called sodium borate, disodium tetraborate, or sodium tetraborate. You may also have heard of boric acid, which is created by blending borax with an acid like sulfuric or hydrochloric acid.

Is Borax toxic to cats?

Borax is toxic for cats, and it can be harmful to people, too.

Shaded siberian cat
Image By: Nils Jacobi, Shutterstock

The Safety Data Sheet from the American Borate Company, which manufactures and distributes borax in the U.S.A., states that borax is a throat and lung irritant if the powder is inhaled. It’s also a major eye irritant. In animal studies, it’s been shown that it can cause reproductive damage and developmental issues if ingested in high doses.

You should never put borax on your cat’s skin. It can lead to serious health consequences for your cat, including:

  • Vomiting
  • Skin irritation
  • Diarrhea
  • Excessive thirst
  • Respiratory problems
  • Redness around the eyes
  • Renal failure
  • Stomach pains

If your cat is showing any of these signs, and you’ve recently used borax or boric acid in the house, call your vet immediately. They may want to put your cat on an IV drip to reduce the chance of their kidneys becoming damaged.

Borax as a flea treatment

We’ve already briefly covered that borax isn’t safe to use around cats, but is it effective as a flea treatment? Borax kills fleas and dehydrates their local environment.

It can be sprinkled on carpets and then left for up to 2 days before vacuuming it away. It will kill fleas and larvae but not eggs, so further treatments might be required.

If you have broken skin while using borax, you could end up with local irritation if you get any borax powder on the area. Breathing in the powder can also be harmful in large amounts.

Borax and boric acid can bleach your carpets and upholstery if it’s left in contact for too long. The effect may be more pronounced with boric acid since it has been combined with other chemicals.

borax and washing soda
Image By: Pixabay


Wrapping it up

The Pet Poison Helpline suggests only using a product on or around your cat that has been specifically created and labeled as safe to use on cats! Borax is not recommended for use on cats, so while you might think that you’re using a “natural” product as a home remedy, you could be putting your cat’s life at risk.

If you keep borax at home, it’s safest to keep it in a well-sealed container out of reach of cats and children. If you use it to remove fleas from surfaces like carpet, keep your cat well away from the room for as long as possible. Using a vet-approved solution for dealing with a flea infestation is far safer than using borax.

Featured Image Credit: JK Sulit, Shutterstock

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