On top of toners, serums and moisturisers, it’s interesting to see that hypochlorous acid sprays have found their way into the routines of beauty aficionados worldwide. We see it as a main ingredient in the likes of Tower 28’s SOS Spray—a recent fan-favourite on Tiktok. But what’s the deal with hypochlorous acid?
Originally developed as a wound-cleaning spray, it first entered the online public consciousness when it was listed as an effective disinfectant against Covid-19. People quickly realized that the formula is gentle enough to spray directly on the skin while also possessing anti-inflammatory and anti-microbial properties—calming redness, eczema and even helping to prevent breakouts.
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Now hailed as a sort of cure-all on social media, there are plenty of reasons why you should carry around this product in your bag. Spritz it on your bedding to prevent back acne, or mist a generous amount on your face to calm breakouts. On a flight, a quick spray can help keep your face feeling fresh during long journeys, ultimately working against nasty airplane air.
But as miraculous as it sounds, not all formulations are created equal. There are specific ways to use it—most importantly, never apply it to damp skin, which can reduce its effectiveness.
Still sceptical? We ask Dr Stephanie Ho, consultant dermatologist and skin specialist at Stephanie Ho Dermatology, to find out just how effective hypochlorous sprays really are and how to use them correctly.
What is hypochlorous acid and how does it benefit the skin?
Hypochlorous acid is naturally produced through the body’s innate immune response. It is a broad spectrum anti-microbial agent that acts against harmful bacteria, viruses, and fungi, while also helping to reduce inflammation and promote healing. Hypochlorous acid is able to combine its broad-spectrum antimicrobial efficacy with a high level of tolerability on skin and mucosal surfaces. Its applications in dermatology are wide-ranging, with notable benefits for the skin. Beyond its antimicrobial action—helping to reduce bacteria, viruses, and fungal load—it also carries strong anti-inflammatory properties, easing itch, redness, and irritation. In addition, it supports wound healing and contributes to scar reduction, making it a versatile solution in skin health.
Studies have shown hypochlorous acid to be effective in improving eczema associated itching, treatment of acne and seborrheic dermatitis.
Is hypochlorous acid safe to use on the face? And is it gentle enough to treat acne?
Yes. As it has a low pH that’s compatible with our skin barrier and is non-toxic, it is safe to use daily on the skin of our face or body. It is often used in the form of sprays or mists for cleansing, soothing and reducing irritation. It can be a helpful adjunct in the treatment of acne by reducing the skin’s microbial load and downregulation of local inflammatory mediators. It is gentler than traditional acne treatments such as benzoyl peroxide or retinoids.
Is hypochlorous acid suitable for all skin types?
Yes, hypochlorous acid is tolerated by most skin types. However I would use it with caution in patients with very sensitive skin or who has open wounds or an obvious skin infection, as these patients will likely require treatment with an antibiotic agent. It is most often prescribed for patients with inflamed, irritated or itchy skin who require an antimicrobial formulation that is easy to apply, soothing and has a low risk of irritation.
What would a negative reaction to hypochlorous acid look like?
While rare, reactions can happen—and may present with redness, stinging or burning, itchiness or dry and tight skin. If that happens, discontinue use and check for additives such as fragrance, alcohol, or preservatives in the hypochlorous acid spray.
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What are some ingredients to avoid or look out for when looking for a hypochlorous acid spray in the market?
Avoid sprays with:
- Added fragrance or essential oils, which can irritate the skin.
- High levels of alcohol which is drying, and counteracts the gentleness of hypochlorous acid.
- Harsh preservatives or stabilizers if you have sensitive skin.
Instead, look for:
- A minimal ingredient list: often just purified water and stabilized hypochlorous acid.
- pH-balanced formulations.
Online, people are using hypochlorous acid sprays in various ways. How helpful is it?
I think using hypochlorous acid sprays in such scenarios can be helpful. On bedding, it may help reduce bacteria and allergens. Mid-flight, it refreshes and hydrates the face while protecting against bacteria in dry, recirculated cabin air. Even in the gym, spraying hypochlorous acid on equipment acts as a gentle yet effective disinfectant.
Users recommend applying hypochlorous acid on a clean, dry face. Would this be the optimal way to apply it?
Yes. Apply it on clean, dry skin. Mist evenly, let it absorb for around 30 seconds, then follow with a serum or moisturizer. It can also be used throughout the day on bare skin or even over makeup as a refresher.
