a big fluffy cat

Q. I’d like to relate my experience with 20 Mule Team Borax, which my vet suggested after I had problems with pesticides. He said I’d drop dead if I kept using flea sprays, as I’m extra sensitive to such things.

My indoor kitten came from the pound absolutely loaded with fleas. I put Borax on the carpet and carefully vacuumed it up. It worked beautifully and I haven’t had to do the Borax treatment again. I very rarely find a flea on my cat even though outdoor cats come near her on the screen porch. The powder did not make her sick, nor did it make my bronchitis flare up, so I’m sold on 20 Mule Team Borax.

A. Thanks for your story. We have heard from many readers who wanted to know whether Borax was really toxic to cats, as they read in our column. To say we are confused would be putting it mildly. Borax is sodium borate, which is not the same as boric acid. Boric acid is used as a pesticide, while borax is not. (This is not meant to dispute your report that 20-Mule Team Borax got rid of your kitten’s fleas.)

Boric acid can be used for flea control but it should only be used in areas that cats or small children will not come into direct contact with it. Here is a story from another reader of our newspaper column:

“I just finished reading your column about using borax for flea control. Let me tell you what happened with our cat. Our 15-year-old Siamese started having seizures. Tests revealed a tumor in the brain. Surgery was successful and she is now doing well.

“When the tissue was sent for analysis at the pathology lab they had trouble figuring out the exact components of the specimen. Further study revealed it was a granulomatous tumor caused by inhaling boric acid.

“We had used a well-known commercial product on our carpet to control fleas. Needless to say, we will never use boric acid again.”

Another reader recommended spreading borax on the carpet and carefully vacuuming it up. The residue was supposed to solve a flea problem. Regular, even daily, vacuuming (with or without borax) can be an excellent way to get rid of fleas. The vacuum cleaner bag should be removed from the house immediately after each cleaning so that the fleas do not escape. Diatomaceaous earth can also be used for flea control, but it too should be applied where the cat cannot get to it and breathe it in. A veterinary pharmacist has told us that any powder can be a problem if a cat inhales it regularly. Some exterminators use sodium polyborate, which probably should not be applied where the cat can be in direct contact with it.

After all this, the bottom line seems to be that you should always check with your vet to determine the safest flea control method for your pet!

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  1. Adrian
    Houston Tx

    The story says the cat got a tumor from boric acid which is not the same as borax!!! They’re two totally different things.

    • Nic
      Pittsburgh, PA

      They are not totally different things, quite similar, actually. Boric acid is released in small quantities by borax.

  2. nylene evans

    I just have to share my story. I had moved in a house and not knowing that I was about to fight a battle of fleas in this house.. I was fighting and cleaning and tried everything I possibly could think of to kill the infestation of fleas..they took over the house..and.my poor cats..indoor cats that have never been outside…well came across a website to try to find something that will actually work. ..well the borax I went and bought and used it in the house…I was amazed how well it worked!!!! I seen so much fleas die as I swept…I am ecstatic. .I will never use anything but the borax.

  3. Mona Bridges

    I know that everyone uses Borax for different purposes around the house, I also use it mainly for cleaning but also against pests like mice and cockroaches. I am sure that it helps with the fleas problem but in my opinion the best is to keep it away of pets. Cleaning your cat with Borax can’t be good! I don’t know any natural way to get rid of fleas and honestly as I know how tough these animals are I recommend using Frontline or something else that works on the same principle.

  4. Lucille
    Monticello, IN

    We have 7 cats. Fleas, as everyone knows, have been particularly bad this summer. If Borax isn’t a good idea, what other natural flea remedies are available? The internal flea treatments don’t seem to do the job, and I am loathed to fill my friends with chemicals.

    • Brandy
      Perkinston, MS

      Hi. Just my 2cents… ;-)
      Currently we have one dog and three cats, and zero fleas. All I do is rub raw organic virgin coconut oil into their coats and have begun putting it into their food daily. One of MANY benefits is flea control. Thanks

  5. Ellen
    Miami, Fl.

    I’ve been using borax soap powder for many years.I sprinkle it everywhere the cats are.It does work on fleas. I’ve never seen any problems with the cats after lying or rolling where borax is, but flea infestations are very common in Florida, hot, humid weather, and my cats are indoor cats, but fleas can be brought in on our shoes, sneakers, because we walk through the grass in our complex, and there are also many ferals in the area that we feed. I also use AdvantageII on them once a month. But the flea problem never ends, sadly!

  6. Steve
    Beaverton, Oregon

    I use Borax, maple syrup and water to kill ants. They love it. The box says Sodium Tetraborate. It is mined as a salt from Death Valley. In the sixties, the TV commercials for it had a real 20 mule team pulling a wagon. I have 2 little dogs and 2 cats. I was worried if they ate the ant poison it may harm them. I use about a teaspoon in a couple ounces of water and syrup. I put it in small pill bottle lids. I hope that small amount won’t hurt the pets.

  7. Wanda
    South Georgia

    I used Frontline Plus (because Advantage has reviews of death) on 3 dogs and 1 cat and they still have fleas. Since I started fostering dogs for the local humane society, I’ve developed the problem with fleas. A friend told me about the 20 Mule Borax. I put it throughout my house rubbing it into the carpet with a broom. I put some in a sock and rubbed it on the animals. NONE of them have gotten sick. The flea issue is getting better. I will continue to use this product.

  8. Brandy

    I think a couple hours would be sufficient. If you don’t have a problem w/ your furniture, I would think just treating the rug would do it.

  9. Andi

    I literally just bought a box of 20 mule borax cause a friend told me about it.. I have a 10 week old toy poodle and an 11 year old chihuahua. I have hard wood floors and one rug.. If I just took the rug out and beat it and swept the floors really good and Swiffer mopped would that be good enough to not harm them and also what is the shortest amount of time I should leave it on? I have nowhere to take them and the room I would have to lock them in gets pretty hot (I live in an old house with no central heat and air).

  10. LM

    I had a bad infestation in my back bedroom where I kept a feral cat. Never noticed fleas until cat passed. I am using 20 Mule Team Borax but I have left down for one month on hard wood floors. I also have a light with sticky pad, they are great. There are less and less fleas and they are getting smaller and smaller.
    I am just about ready to clean up Borax. I did not want to reapply again if I could avoid that. I understand it takes a long time to get rid of fleas because of the life cycle of the flea. The eggs and larva can live up to a year before hatching. I do not think the borax works quickly, but I do think it works. I have been fortunate that I could keep the room closed off and not use during treatment.

  11. tk

    I can’t believe ANYONE in their right mind would use Sevin Dust on ANY living thing!! WOW!! It says right on DO NOT APPLY DIRECTLY TO ANIMALS!! Sevin Dust is a very powerful chemical PESTICIDE!! Is your cat still alive??? SO glad to hear you have switched even if only due to cost!
    Please people DO NOT EVER USE SEVIN DUST ON YOUR PETS! IF POSSIBLE DON’T USE IT AT ALL!! FOOD GRADE Diatomaceous Earth is absolutely 100% chemical free, can be sprinkled lightly on your pet (avoiding nose and eyes), your carpet, baseboards and pet bedding. DE is nothing more than fossilized diatomes.. 100% natural. NOT a chemical made in a factory meant to KILL living beings!!

  12. NK

    I just left my vet’s office. She said Frontline does not work any more. When it first came on the market, it worked okay, but it never did kill all the fleas and they became resistant to it. On the other hand, she said Advantage still works as good now as it did when it first came out because it kills all the fleas. This makes sense to me as a few days prior to speaking with my vet, I had put Frontline Plus on my dog. The fleas were just as thick and horrible a few days later as they had been before treatment. I was wondering what the heck was going on, now I know.

  13. Cynthia

    I have a very tight weave berber carpet in my home. I applied the borax powder to kill fleas. I am vacuuming daily but find that because of the type of carpet I have I was not able to vacuum up all the borax and now each time I vacuum I experience burning eyes and can taste the borax in my mouth from the borax Dust. Has anyone else experienced this?

  14. Danielle

    I would like to mention that boric acid is very different than borax. Yes borax contains a very small amount of boric acid but is definitely not the same as boric acid that is used as an insecticide.

  15. Michelle

    Oh my gosh! Please do not use pool quality diatomaceous earth around animals! Get food quality diatomaceous earth.

  16. Ddrhl

    The only thing that worked for us was Terminix…call in the professionals. The cost was covered because we’d used FrontLine Plus through our vet and still had fleas within 3 months of use. They had to come twice, but that did it. Best wishes to you. I know how awful it is when your home is not a haven.

  17. RLS

    Borax is used in flux for soldering hard metals, also used in washing detergent, also used in certain insecticides, but rarely sold in stores as an off the shelf product.

    • Judy

      I buy mine at Safeway and other stores big boxes of it and most stores sell it, I use it for fleas and for washing clothing too. Used it for 30 years for fleas and litter box (just a little in the litter).

  18. Anastasia

    I used a flea dip on my cat and it caused irreparable kidney damage. It caused him to die prematurely; would not recommend any strong chemicals on an animals body; just like humans, everything we put on our bodies.

    • Arcanalia witch
      North Carolina

      Where I live borax is always available at the grocery store in the laundry detergent aisle. It used to be called 20 Mule Team Borax & had the picture of the wagon being pulled by 20 mules, as it was mined in the desert. The label has changed, but not the product.

  19. Lynne

    we have a flea problem this year more then we ever have. I live on the east coast and in the northern section so it’s been a bit hot but not too bad. We’ve had 3 or 4 “heat waves ( over 90 degrees 3days in a row) “so whoopie.
    Anyhow I have flea bathed, powered, collared, used drops and combed out my cat and dog so far. They are much better however my issue our basement.We found out we have the problem because (My son is newly diabetic) he is the one they are attracted to the most. NOW i say that because he goes down to do the laundry or to get something and they jump on him. The rest of us go down and maybe only get 1 or none.
    We have a 1300 sq.ft home and we have put 3 can bombs in the main part of the house and 3 in our basement ( major overkill) and they lil buggers lived through it. We just emptied 3 boxes of BORAX on the floors and rugs in the basement and all over upstairs and on the furniture too. The BORAX upstairs was down for 3 days before vacuuming as we did it before we left for camping. When we came home we vacuumed it up ( just the upstairs) . NEver found a dead flea but never really inspected it that closely either. To this day ( now 10 days later) we still have fleas in the basement and we have NOT even vacuumed up the BORAX YET.
    We figured we just won;t go down there unless we have to and we will leave it longer to work better. Well its not. SO NOW WHAT SHOULD WE DO????? Those lil BLEEPS are still alive. My husband figured if they have a life cycle of 3 days or even 7 days they would hatch and then die. NOPE. Oh the other thing down stairs is a flea trap ( light with a stick pad) yup they go to that but really i don;t like leaving a light on all day & night but we have to. NOTHING IS WORKING . They aren’t really bad but they are really annoying because everytime we go down there we have to “CHECK OURSELVES” to make sure we didn;t bring any hitchhikers up with us. SUGGESTIONS PLEASE!!!!!!!!!!!!!

  20. Troy

    Borax and Boric acid ARE NOT THE SAME THING!

    • Arcanalia witch

      Try putting small containers of water around on the basement floor. Fleas need moisture to live, so they are staying in your laundry area for this reason. They will jump in the water, but have no solid surface from which to jump out. You could even put a little sugar in to attract other bugs, and a couple drops of white vinegar to kill them. To dispose, pour down the drain followed by HOT water, or pour outdoors, away from the house. Make sure to keep at least a couple inches deep of water.

    • Marsa Herod

      Try putting down shallow bowls of water with a few drops of dish washing liquid in it. Sit them in different areas around the room. They work best if a light is shining near them. The fleas go for the water and then they can’t get out because of the soap.

  21. Marie

    Do not use any so called safe Pyrethrin or even worse the synthetic Permethrin both can seriously harm a CAT. From drooling, vomiting, tremors, to full blown seizures and death. Do not ever use ”extra” for realy bad infestations- it may kill your pet. Dogs can be harmed too but they fare better. Also be cautious if your cat loves your dog and licks them or rubs on it; the toxic product can be spred that way.

  22. 3ringquercus

    Our cat developed neurological symptoms–a scary head tic–after using Revolution and Frontline. The vet determined that (as a representative from Frontline confirmed) the cat is “allergic” to one of the chemicals in the product, possibly one of the inert ingredients since she reacted to both products. My vet also doesn’t like the flea-dips for animals, says they’re very toxic, so…Dawn Kitteh-Washing Liquid and 20 Mule Team it is.

  23. Ddrhl

    After our Terminix’ second visit, the fleas were gone.
    If you are only reading recent posts on this thread, you are missing important info on the difference between Borax and Boric Acid…read the entire thread…it’s not that long.
    FYI…after spreading DE outside my house, one of my cats developed a horrendous sounding cough…deep, low and throaty. The vet says she’s fine which surprised me considering how high her voice actually is.

  24. DSW

    do I need to add salt? don’t want to kill grass.

  25. DSW

    will borax harm my cats? I have a dog door so my 3 cats and small dog can go into fenced yard when needed,how soon can I let them out after using borax on yard?

  26. KMK

    Thank you. The borax vs boric acid comment makes more sense than the first article. Different ingredients.

    • Arcanalia witch

      I had a completely screened-in porch built for my indoor cats (about 4 feet above ground) and there are free-roaming neighbors cats coming around and dropping off fleas. Will the borax work on the grass and ground?

  27. Brandy

    You do need to vacuum the borax up from the furniture. Remember to keep pets and humans out of areas you are treating. Leave it down for a couple hours, then vacuum it up. It has been effective for us, even though we have 9 cats (!)

  28. tina

    Thanks so much for your reply, Brandy! So any type of furniture that isn’t leather… ok to leave it in the cushions and not vacuum it up, cats love the sofa and I guess the seat pads/cushions (they are removable) on the chairs too? Unfortunately my cats love to go out, and it is very hard to keep them flea free, but they usually die since I do use the once a month topical…. even though I am not happy with it, really, nothing else but Revolution/Advantage/Frontline….

  29. Brandy

    No, I don’t think you need to put it down on tile/flooring- those type of surfaces can usually be vacuumed and don’t harbor flea eggs. Don’t forget to treat furniture w/ fabric coverings, though.
    (PBA- yes, I had a cat that got very ill after being dipped at the vet’s, and another one that was obviously sick after I used a home remedy- Avon’ Skin-so-soft diluted w/ water. I never had the first cat dipped again, and the 2nd one I gave another bath to, and he was okay after that. Cats are much more susceptible to chemicals than dogs, I have read.)

  30. tina

    Wow, I am so glad I came across this site, all of the stories, tips and advice are so invaluable.
    Brandy, I much appreciate everything you said and suggested. I do have a question, I live in Florida where there is an open floor plan, and the flooring is tile in the kitchen/dining/living room areas…two bedrooms do have cheap builder grade carpet which I did put Borax down this morning….my question is do I have to put it down on the tile also?

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