Should You Put Hydrogen Peroxide on Cuts and Why Does It Fizz?

Neal H. asks: Why do we put hydrogen peroxide on our cuts?

cleaning-wound-hydrogen-peroxideAs a child, did you ever skin your knee and fear telling your parents, afraid of your mom breaking out the brown bottle of pain containing hydrogen peroxide to “help heal” your wound? Given the agony it caused, you might have wondered whether the fizzing liquid was actually helping, and why hydrogen peroxide bubbles when it comes in contact with your skin. If you’re still wondering today, well, wonder no more.

To begin with, hydrogen peroxide does indeed kill bacteria, viruses, fungi and a whole host of pathogens thanks to the fact that it is a powerful oxidizing agent. So in theory it seems like a great idea to pour it on a fresh cut to help prevent infection. It turns out, however, that while this has been a staple home treatment for cleaning various cuts and abrasions for nearly a century, you probably shouldn’t use hydrogen peroxide to disinfect your wounds. To better understand why not, we’ll need to look at what hydrogen peroxide is and how it manages to kill microorganisms.

hydrogen-peroxideChemically speaking, hydrogen peroxide, which is a naturally occurring molecule within the human body, is two parts hydrogen and two parts oxygen (H2O2), with the molecule held together by the two oxygen atoms. As a result of these oxygen atoms having a very weak bond, the molecule breaks down rather easily, potentially introducing free radicals into your system. Left unchecked, this would all result in a host of problems within the human body.

In fact, because hydrogen peroxide’s claim to fame is primarily its great oxidizing effect, up until relatively recently it was thought that its presence in the body had only damaging effects. However, recent research, such as that performed by the German Cancer Research Center (Deutsches Krebsforschungszentrum) in 2014 was able to show that hydrogen peroxide is an essential chemical messenger helping the body’s cells respond to outside hormones and growth factors. As Dr. Tobias Dick sums up, “We know today that the body’s own H2O2 is vital for signal processing in a healthy organism.”

That said, the level of H2O2 must be maintained in a specific range (between 0.05 micromol/l and 117 micromol/l in exhaled breath, and in human fluid). Too much and the damaging effects of oxidation will cause countless problems that can result in cell death, among other issues.

Enter the enzyme catalase, which is found in almost all living things. Catalase circulates throughout the cell, waiting to come into contact with the H2O2 being produced by cellular respiration. Once in contact, it rapidly converts it into water and oxygen (via two H2O2 molecules becoming two H2O (water) molecules and one O2 (dioxygen) molecule).

In fact, the catalase is so good at its job, that it has one of the highest chemical conversion rates of any enzyme. A single catalase molecule can convert millions of hydrogen peroxide molecules every second. (It is this water and oxygen being rapidly produced that results in the fizzing/bubbling effect you see when the hydrogen peroxide comes in contact with the catalase.)  However, even with this efficiency, residual hydrogen peroxide will remain, allowing your body to maintain the low concentration of hydrogen peroxide required for normal protein signaling, while keeping it from reaching toxic levels that can destroy a cell.

Like all living things, bacteria, viruses, and many other pathogens have a myriad of chemical reactions taking place within their cells.  Just as the oxidizing effects of hydrogen peroxide can ultimately potentially interrupt these processes, it can also do the same to bacterial cells. Thus, if this oxidizing agent is in high enough concentration, the result is a halt to normal cellular processes resulting in the death of the pathogen.

So why the controversy today on whether you should use hydrogen peroxide on wounds? As just mentioned, this oxidizing agent will also kill healthy human cells in sufficient concentration. Beyond this, it’s also thought that it may slow down the mechanisms of healing because it interferes with the normal scaffolding processes involved with repairing skin damage. (This interruption can also potentially lead to increased scarring, see: How Scars Form.)

This is all not to mention that if the oxygen gas produced by the large amount of hydrogen peroxide coming in contact with the catalase enters your blood stream, it can circulate throughout your body leading to countless medical problems like heart attack, stroke, or pulmonary embolus.  While you might think this couldn’t possibly happen, hydrogen peroxide used as a topical disinfectant has been implicated in several fatal and near fatal incidents due to this oxygen gas being introduced into the bloodstream.  However, as yet it’s not entirely clear how the oxygen is getting there. It may be that excess oxygen enters the capillary beds themselves, or that H2O2 (hydrogen peroxide) molecules get absorbed into the bloodstream and then, in such relatively high concentration, create the oxygen embolus. Whatever the mechanism, the potentially life threatening complication remains.

So in the end, thanks to the propensity of hydrogen peroxide to cause damage to healthy tissue, combined with the very slight risk of oxygen emboli after pouring it on a cut, the use of hydrogen peroxide to clean wounds is usually not recommended anymore, presumably much to the relief of six year olds the world over. As for what you should do when cleaning wounds, most doctors will point out simply using normal saline, a little elbow grease, and some over the counter topical antibacterial products will have a much greater chance of preventing infection then the hydrogen peroxide would anyway. Pure Mānuka honey anyone?

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  • I know too many people who ended up with bad infections when using the ascribed washing and antibacterial cream treatment of cuts, including myself. HP always works and has cleared up raging infections. Yes, I do have scars (though not bad considering how bad some of my gashes have been) but considering the alternative in this day of flesh eating bacteria, I will take the scars. I always suspect big pharma of promoting the “new” and “modern” cure to the old tried and true. I’m keeping HP in my medicine cabinet but thanks for the well written description of how HP works.

    • Jonathan Tucker

      I used Clorox in the past to clean surface wounds and it worked for me (relatively small scarring compared to not using it), but that doesn’t mean it’s good for the body. The point of the article was to let you know that it CAN cause issues in the body and show how it scientifically happens. What you do and what works for you is none of their concern. . .

  • The main problem with the conclusions in this article are that the supposed damaging effects are so poorly supported by evidence. AND the one BIG advantage of using HP is exactly the oxidizing/foaming power this author denigrates – this immediately discourages the growth of anaerobic bacteria/spores introduced into the wound with dirt (think tetanus, etc.), especially deep puncture wounds. Keeping such wounds cleaned out and bacteria-free while they heal from the inside out on a free-ranging cow or horse is extremely difficult. Experience with the various livestock I have kept over the years illustrated this nicely. A cheap syringe (no needle) full of HP used to clean out the wound a couple times a day made all the difference between a festering mess and a wound that healed up nicely. This same technique was no doubt quite useful on humans in the pre-antibiotic days. And given the rapid expansion of antibiotic-resistant bacteria today, I would say we would be remiss not to keep this treatment in our arsenal.

  • Hint from the folks at my local blood donation center: HP is excellent for eliminating blood stains from textiles. Dribble some drops directly on the [fresh] blood stain, watch it fizz the blood out of the fibers. (May need multiple application for major stains.) Then launder as usual.

  • If you want to use hydrogen peroxide for this purpose, please take care of your safety while handling this chemical. In addition, when you make a 3% hydrogen peroxide from 35%, wear appropriate personal protective equipment such as eye goggle and vinyl gloves.
    Remember that 35% hydrogen peroxide is a hazardous chemical, which is a strong oxidizing agent. It may cause your eyes to be blind and irritates your skin!

    • HP has always helped cuts and open wounds. I do not agree with the majority of the article because of the HP purpose. Although it has been used for decades, it serves as a cleansing part so yes it definately does the job! Yes HP works and is definately needed on cuts!!!

  • This article is typical of an intentional distracting focus on the veins of the leaves of the trees to make you blind to the forest right in front of you.

    A small bottle of hyrogen peroxide costs roughly about $1.

    And this must gall the hell out of doctors and the pharmacuetical industry that would obviously love to make a fortune off you by getting you to use their incredibly costly products, which in many cases, like this, first require to fraudulently over exaggerate the dangers of a simple and very inexpensive home remedy.

    Otherwise known as fear marketing.

    Peroxide has worked for decades and decades to sterile superficial wounds for a reason. It works!

    And here’s another tip that will piss off doctors and the pharmacuetical industry making a fortune off high cost acne medicine. Pour a little into the cap and dip the tip of Qtip into it and then dab the tip onto a pimple, and watch that pimple clear up super quick. Because the hydrogen peroxide kills the bacteria in the pimple. As it was designed to do.

    And if you want to help clear up your abnormal acne on a larger scale, try giving up cell phone use against or near your face, which is exposing your face to completely abnormal digitally pulsed microwave electromagnetic radiation that interferes with the correct functioning of the electrical fields of the molecules that make up every part of your cells, from the cell membrane to the DNA in the nucleus. And
    subsequently progressively interferes with the protection of the cells of your skin that were never designed to correctly function with this completely abnormal manmade EMR, that never existed while human beings and their biological systems evolved over the course of millions of years.

    And aside from a significant increase in acne, there has also been a similar abnormal increase in psoriasis and skin cancer in the population that has been directly keeping pace with the exponential introduction of each new round of computers and cell phones and wireless devices andemissions of completely abnormal EMR from them over the past decades.

    But you’ll have to get a little educated on your own about that subject. And I wish you the best of luck.

    • Mr.Gary, I really thank you for being brave and saying the truth, the Farma companys ( LEGAL Mafia) likes to keep us in fear and confuses people so they wouldn’t loose business,

    • No u dumbass conspiracy theories are perpetrated by uninformed,ignorant,trolling,
      people like u…these are actual scientific facts…do ur research…I have a medical condition that causes severe rashes and open wounds…antibacterial soap will also do the job…also about 1$…that’s what my doc. Told me to use to prevent infection…not buy their pills…and also told me pretty much everything this article says…that was when I was 17…now 45…been know in science for years…seems to me the HP people keep pushing their inferior worthless product for profit…not the pharmaceutical companies…idiot…!

  • As soon as the author started talking about the “brown bottle of pain”, he lost all credibility.
    I have used hydrogen peroxide on cuts, scratches, scrapes and burns for most of my 55 years. Never once has it stung. He must be confusing peroxide with alcohol.
    There may be good reasons not to use peroxide on wounds, but avoiding pain of application isn’t one of them

    • Daven Hiskey

      I’m going to have to disagree with you on that one. It was the brown bottle of fizzy pain. Alcohol doesn’t fizz. 🙂