What Is Hypochlorous Acid Spray?
Hypochlorous acid spray is a weak acid made from hydrogen, oxygen, and chlorine. It’s been used for a long time as a disinfectant and is said to be 100 times better than bleach at killing bacteria. Recently, it has become popular as a skin care product, used to calm skin and kill bacteria that can cause acne flares.
Your body makes hypochlorous acid (HOCl) when you get hurt or sick. It's part of how your immune system fights germs. It breaks down the outer layer of bacteria and viruses to help get rid of them.
Hypochlorous acid and bleach (sodium hypochlorite) come from the same basic ingredients: hydrogen, oxygen, and chlorine. And they both work by breaking down the protective outer layer of bacteria and viruses. But they’re not the same. Bleach is a base. It’s harsh and can irritate your skin, eyes, and lungs. Hypochlorous acid is a weak acid that’s safe to use on the skin.
History of Hypochlorous Acid
In 1834, a French chemist named Antoine Jérôme Balard produced hypochlorous acid in a laboratory for the first time. The process involves passing a small electric current through salty water.
In the early 1900s, scientists discovered that hypochlorous acid fights off bacteria. It was especially useful during World Wars I and II, when medical teams applied it to soldiers' wounds to prevent infection.
During World War I, doctors also started using it to treat throat infections such as diphtheria and scarlet fever.
In the 1940s, during World War II, hospitals in London sprayed a mist of hypochlorous acid into the air to kill germs and stop the spread of infections. It acted like an early version of the air sanitizer sprays we see today.
During the COVID-19 pandemic, hypochlorous acid became popular as a safe disinfecting agent.
What Is Hypochlorous Acid Spray Used For?
Hypochlorous acid spray has a wide range of uses:
Eye infections. Doctors can use hypochlorous acid to treat blepharitis. This is a condition that makes your eyelids red and uncomfortable, often due to a buildup of bacteria at the base of your eyelashes. Hypochlorous acid treats it by reducing the number of bacteria on the skin around the eyes.
Surface disinfection. Hypochlorous acid can also be used to clean and disinfect surfaces in medical settings. In one study, a surgery room cleaned with it had much less bacteria than a similar room that was cleaned with standard disinfectants.
Wound disinfection and healing. Hypochlorous acid can kill bacteria that cause infections. Lab tests with a 0.01% hypochlorous acid solution have found that it kills bacteria in wounds as well as or better than common disinfectants like povidone-iodine, chlorhexidine gluconate, and 70% isopropyl alcohol.
Because of its antibacterial properties, doctors use hypochlorous acid to disinfect open wounds and diabetic ulcers. It reduces the number of harmful bacteria in a wound, which lowers the risk of infection and the need for antibiotics.
Researchers have also compared hypochlorous acid with saline for the treatment of complex or infected wounds. They found that people who used HOCl needed fewer surgeries, healed faster, and had shorter hospital stays than those who used saline treatments. Studies so far have been very small, so we need more research to know for sure if these results are true for large numbers of people.
While traditional antiseptics can damage skin cells and slow down wound healing, hypochlorous acid has minimal side effects.
Nasal rinse. Research has shown that hypochlorous acid nasal spray improves the symptoms of chronic nasal inflammation (rhinosinusitis) as well as saline with no side effects. A nasal spray with hypochlorous acid works about as well as regular saline rinses to help with recovery after sinus surgery.
Hypochlorous acid spray for skin
Hypochlorous acid has become a trendy beauty product, one that even people with sensitive skin can use. Online influencers promote its healing properties. Skin care companies sell product lines with it in spray, lotion, and serum forms, by itself or combined with other ingredients.
Hypochlorous acid can benefit skin in a number of ways:
Acne. Acne isn’t an infectious condition, but certain bacteria found on the skin can cause acne. They make enzymes that act with the oils in your skin to create fatty acids. These acids can thicken and clog pores. Hypochlorous acid fights those bacteria. In a study, people with mild to moderate acne found that it worked just as well as benzoyl peroxide, a go-to treatment for acne.
Scar repair. Research looking at adults with different types of scars found that treatment with a hypochlorous acid-based gel led to greater improvements in how the scar looked after 16 weeks, compared to standard treatment with silicone gel.
Inflammatory skin conditions. Hypochlorous acid helps calm down the chemicals in your body that cause swelling and itching. This is why doctors use it to treat inflammatory skin conditions like eczema (atopic dermatitis) and seborrheic dermatitis (a condition that causes flaky, itchy skin).
In a study of people with eczema, most of those treated with hypochlorous acid noticed less itching within three days. Besides lowering inflammation, hypochlorous acid also fights the skin bacteria that cause eczema flare-ups.
In another small study of people with mild to moderate seborrheic dermatitis on the face and scalp, treatment with a hypochlorous acid-based gel improved symptoms like burning, stinging, and itching after two weeks, with even greater improvement by week four. Only one person had increased redness and flaking after treatment.
Most of the studies on the effects of hypochlorous acid have been very small. We need more studies that involve many more people to understand completely how well it works.
Is Hypochlorous Acid Safe?
Hypochlorous acid has proven to be safe and free from side effects for most people. At low concentrations (about 0.008%), it usually works well and is well tolerated, according to Adam Friedman, MD, a professor and chair of dermatology at George Washington University School of Medicine and Health Sciences. But "Prolonged exposure can increase the risk for irritation," he notes.
It’s best not to pair it with strong exfoliants (products designed to remove dead cells from the surface of the skin). Doing this might make your skin more sensitive. Some examples of exfoliants include lactic acid, glycolic acid, and salicylic acid.
Friedman suggests choosing a product with a low concentration (about 0.008%) and doing a patch test before using it. This is especially important if you have sensitive skin or had allergic reactions in the past. He also recommends using it for a short time only.
Takeaways
Hypochlorous acid is a weak acid used to prevent and treat infections, promote wound healing, and treat skin conditions like eczema and acne. It fights off bacteria and reduces inflammation. It’s generally safe to use at low concentrations, but it may cause irritation if you use it for too long.
Hypochlorous Acid Spray FAQs
Do dermatologists recommend hypochlorous acid?
Yes, dermatologists recommend hypochlorous acid, but there are things you should do to use it safely. Choose a product with a low concentration (~0.008%). Do a patch test before using it, especially if you have sensitive skin or have had allergic reactions in the past. Use it for a short time. If you have any side effects, stop using it right away.
What should you not use hypochlorous acid with?
If you combine it with strong exfoliants, it may make your skin more sensitive.
What are the side effects of hypochlorous acid?
If used too much, it can cause skin irritation, allergic reactions, and may make itching worse.
Is hypochlorous acid just bleach?
Hypochlorous acid and bleach have the same basic ingredients, and they both kill bacteria and viruses by breaking down their protective outer layer. But bleach is a base that can irritate your skin, eyes, and lungs. Hypochlorous acid is a weak form of an acid that your body makes naturally to fight infection. It’s safe to use on your skin. It can be more effective than bleach for killing bacteria.
Can you overuse hypochlorous acid spray?
Even though hypochlorous acid is mild, you can still overuse it. Using it for too long can upset your skin or make itching worse, so it’s important to follow your doctor’s directions.
