9 Ways to Use Hydrogen Peroxide

Your bottle of hydrogen peroxide deserves more than just sitting in your first-aid kit. This affordable liquid is widely recognized for its medical uses and bleaching hair, but it's also a highly adaptable substance with many other uses to explore.

Hydrogen peroxide (H2O2) is a chemical made of hydrogen and oxygen. This clear liquid acts as a gentle antiseptic and is available in different concentrations: 3 percent (household use), 6 to 10 percent (hair bleaching), 35 percent (food-grade), and 90 percent (industrial). The common 3 percent solution is often found in the characteristic brown bottle.

For many years, healthcare professionals advised using hydrogen peroxide for treating minor cuts and scrapes. This was because it bubbles upon contact with the skin, signaling the destruction of bacteria. However, doctors now recognize that hydrogen peroxide also harms healthy cells, leading many to no longer suggest its use for this purpose. It can also cause damage if it enters your eyes, covers large areas of skin, or is ingested, particularly in the case of food-grade hydrogen peroxide.

But don't worry. Hydrogen peroxide offers numerous other useful applications, some of which you might not have heard of. Here are nine to consider. (Unless otherwise specified, the 3 percent version of hydrogen peroxide is referred to in these examples.)

1. Eliminate Pit Stains

Admit it, those brownish-yellow stains on your armpits are frustrating and embarrassing, especially on a new shirt. You can remove them by mixing one part dishwashing liquid with two parts hydrogen peroxide, applying the solution to the stain for an hour, then washing it in cold water. After drying, you can wear it again. If the stain is stubborn, a gentle scrub with baking soda might be necessary.

2. Cultivate Mushrooms

It may sound unbelievable, but it's true. Hydrogen peroxide — specifically the 35 percent version — can help fight mold infections that threaten your mushrooms. Simply apply a few drops to the fruiting chambers (where mushrooms grow) to instantly increase oxygen levels.

3. Freshen Up Your Dishwasher

Hydrogen peroxide can be used to clean your dishwasher effectively. You can spray it directly inside, let it sit for a bit, and then wipe clean. Alternatively, make a cleaning "bomb" by combining hydrogen peroxide, baking soda, and essential oil. Mix them and form small balls with an ice cream scoop. Let them dry overnight. To use, drop one bomb at the bottom of the dishwasher, then place a mixture of white vinegar and liquid dish soap in a bowl at the top. Run a cycle with the bomb, vinegar, and detergent, and the peroxide will sanitize while the baking soda scrubs and the oil adds a fresh scent.

4. Brighten Almost Everything, from Nails to Grout

Hydrogen peroxide is excellent at brightening and whitening various items, such as stained tiles, grimy grout, and even fingernails. For nails, mix one part hydrogen peroxide with two parts baking soda, then rub the paste onto your nails. Let it sit for 2 to 3 minutes, then rinse off. Voilà! Beautiful, white nails. For grout whitening, you can either apply the hydrogen peroxide directly to the tiles or make a paste with baking soda and scrub it off.

5. Create a Homemade Mouthwash

Hydrogen peroxide is fantastic for oral care. To use it as a mouthwash, dilute it with equal parts water and hydrogen peroxide, then swish for a minute before spitting out (never swallow!). Not only will it kill germs, but it also helps whiten your teeth. It's also great for disinfecting and cleaning dental tools, like toothbrushes, retainers, and mouthguards.

6. Enhance Your Laundry

Forget those costly laundry boosters with "oxy" in the name. Just add a cup of hydrogen peroxide to your washing machine when washing white clothes. It will not only brighten your clothes but also neutralize odors and eliminate stains. You can apply it directly to stains, but be sure to test it on a small patch first if using on darker fabrics.

7. Eradicate Mold and Mildew

As we mentioned earlier, hydrogen peroxide is not only effective against bacteria but also eliminates fungi like mold and mildew. Simply grab a spray bottle filled with hydrogen peroxide and spray it on bathroom surfaces, floors, walls, humidifiers, dehumidifiers, or even the shower curtain. The fizzing sound indicates it's doing its job.

8. Enhance Your Garden

Gardeners swear by hydrogen peroxide as a miracle liquid for plants. It helps control pests, prevent infections on damaged trees, tackle foliage fungus, fight root rot, and boost plant growth. The added oxygen helps roots absorb more nutrients. To repel pests or promote growth, mix one teaspoon of hydrogen peroxide with one cup of water in a spray bottle and mist the plants. For root rot or fungal issues, use one tablespoon per cup of water.

9. Keep Your Food Fresh

Spraying your salad greens with a bit of H2O2 before storing them in the fridge will prevent sogginess for days. You can also use hydrogen peroxide to keep fruits and vegetables fresh by spritzing or soaking them in a solution. Just be sure to wash them thoroughly before eating.

Editor's note: Hydrogen peroxide with a concentration of 3-5 percent is safe to ingest, but higher concentrations (10 percent or more) can be harmful if swallowed. This clarification has been made in the updated version of the article.