What is hypochlorous acid and what is it used for?

According to TikTok, where it is hugely popular, there's a new ingredient to know about because, among other things, it proves to be an excellent post-workout refreshing spray that kills bacteria, fights acne, and reduces redness: hypochlorous acid. Don't be fooled by the name that evokes aggressive household cleaners and abrasive substances. HOCl is a valuable beauty ally that doesn't irritate the skin and is known both for its germicidal power and ease of application. These characteristics, considering the spray format of the products that typically contain it, make it a summer must-have, convenient to keep in your bag and spray as needed to refresh, control skin breakouts, or soothe redness. Here's everything you need to know about hypochlorous acid.

What is Hypochlorous Acid?

Hypochlorous acid is a weak acid that forms when chlorine dissolves in water. It is a very important substance in the immune system found in our bodies, produced by white blood cells to fight bacteria and other invading microorganisms that could be harmful and cause diseases. Discovered in 1834 by French chemist Antoine Jérôme Balard, it was used during World War I, in a version derived from a mixture of bleach and water, to clean and irrigate wounds. Composed of hydrogen, oxygen, and chloride, it offers antimicrobial and anti-inflammatory benefits. When its concentration is correct, it is added to skincare and haircare products as an ideal active ingredient for the most sensitive and inflamed skin.

The Benefits of Hypochlorous Acid for the Skin

As we mentioned, if correctly diluted, hypochlorous acid is harsh on harmful bacteria but gentle on the skin, even on sensitive skin. A significant advantage is wound healing, as it is a powerful killer of bacteria, viruses, and even fungi. By removing organisms that contribute to inflammation and the breakdown of the skin barrier, it helps the skin heal. Safe and gentle, it is excellent to apply to wounds. Its anti-inflammatory and antibacterial properties make it the ideal ingredient for those suffering from acne because it prevents the formation of blemishes, clears pores, prevents pimples, and has a reparative function on the marks of past imperfections. Dermatologists recommend it for people with eczema, rosacea, sunburns, or any time the skin is irritated. A bonus? It also seems to help reduce itching.

Where to Find and How to Use It

Hypochlorous acid is mainly found in facial sprays, lotions, and toners. In all those products that take care of the skin and its barrier before applying treatment. The most popular one? The SOS Daily Rescue Facial Spray by Tower 28, excellent for spraying on the face or scalp because it can help soothe and repair irritated skin. It is very easy to add to the daily skincare routine. Experts recommend using it after cleansing but before moisturizing, in the morning or evening, depending on individual needs, to create a perfect base for absorbing other products. Despite its benefits, it is not recommended to use it as a substitute for other acne treatments based on salicylic or glycolic acid.

Side Effects of Hypochlorous Acid on the Skin

If hypochlorous acid is diluted to the correct concentration, there are no risks for the skin. However, to avoid risks, make sure that the hypochlorous acid products you are using are specifically formulated for the skin. It is advisable to test them on a small area of the skin before regular use to avoid potential skin irritations that high concentrations of hypochlorous acid can cause, which manifest as redness, itching, or burning. Once checked, it is still better to avoid applying it around the eyes and mouth. It is important not to try diluting hypochlorous acid at home to avoid causing chemical burns.