This is the product that put cosmetic hypochlorous acid on the map in the US. The formula is essentially four ingredients — hypochlorous acid in saline water — and that minimalism is the point. It works on essentially any skin type, can be sprayed on broken skin without stinging, and addresses bacterial overgrowth (acne, eczema with S. aureus colonization, post-workout flushing, post-procedure recovery) through a single mechanism the human immune system already uses.
The product that put cosmetic hypochlorous acid on the US map and the foundation Tower 28's whole brand was built around. Four ingredients — saltwater plus hypochlorous acid — used to address acne, eczema, rosacea, post-procedure recovery, and just about any skin condition where bacterial overgrowth or barrier inflammation is a factor. Pricey for what it is, but uniquely well-tolerated.
The case for it
What would change this: A researched evidence row for the lead active would replace this with a verdict.
Same rule for everyone. “Good choice” is the verdict on 1,938 of 45,024 concern verdicts across the catalog; rule F2 decided 1,938 of them. Unchanged since September 5, 2026, engine 5.1.1.
Brand or formulator? Disclose a concentration or correct a fact →
Also listed for Acne, Rosacea, Eczema, Compromised Skin Barrier and Post-Procedure — the actives here (Hypochlorous Acid) are in our research queue for those concerns; there is no verdict until their evidence rows are written. That is a gap in our table, not a mark against the product.
A verdict is DermApproved’s assessment of how well a product’s ingredients fit a concern — never a claim about what the product treats. Evidence dots and collected reviews sit beside it and are never blended in. Rules 0.5.1 · evidence table ev-2026.09-r228 · how we decide
There is a particular kind of skincare product that becomes culturally important not because it's complicated, but because it's correct. The Tower 28 SOS Daily Rescue Facial Spray is one of those. The formula is four ingredients long: electrolyzed water, sodium chloride, sodium hypochlorite, and hypochlorous acid. That is the entire thing. There is no glycerin, no botanical extract, no preservative system, no fragrance. It is functionally saltwater that has been processed to generate hypochlorous acid, and that minimalism is not a marketing position — it's the actual product. The spray exists because Amy Liu, who founded Tower 28 in 2019 because her own eczema made most cosmetics unwearable, was using hypochlorous acid wound-care products from clinical brands and decided the same thing should be available in a format that didn't look like it came from a hospital supply catalog.
The ingredient is interesting enough to deserve a paragraph on its own. Hypochlorous acid (HOCl) is the antimicrobial molecule that human neutrophils produce as part of the immune response to bacterial infection. It has been used in clinical settings since the early 1900s — Dakin's solution, used to clean wounds in World War I, was a hypochlorous acid preparation — and modern formulations are FDA-cleared for wound care. In dermatology specifically, it has been studied for atopic dermatitis (where S. aureus colonization is part of the disease mechanism), inflammatory acne (where C. acnes overgrowth contributes), seborrheic dermatitis, and post-procedure recovery. The selling point versus other antimicrobials is that hypochlorous acid is selective enough to suppress problematic bacteria without wiping out the broader skin microbiome — alcohol, by contrast, kills indiscriminately and disrupts the barrier. Benzoyl peroxide kills C. acnes effectively but irritates and bleaches everything. HOCl is the rare antimicrobial that works without collateral damage, which is why it ended up in the wound clinic in the first place.
Two misconceptions are worth killing here, because both come up constantly. The first: this is not bleach. Household bleach is sodium hypochlorite at high concentration, a different molecule behaving differently; hypochlorous acid at cosmetic strength is the compound your own immune cells manufacture, and the therapeutic window between 'kills bacteria' and 'harms human tissue' is unusually wide. The second: a four-ingredient formula is not an empty one. Most facial mists genuinely are expensive water with marketing attached. This one is a documented antimicrobial in a saline carrier at pH 4.5, which is where the molecule is stable and active.
In use, the spray is unremarkable in exactly the right way. It mists on cool, absorbs almost instantly, has a very faint clean chlorine note that some people notice and others don't, and produces no sting on application — even on broken or sensitized skin. The instructions are 'spray two to three times on cleansed skin, let air dry, continue with your routine,' and that's all there is to do — do not pat it in, just let it evaporate. It can also be used throughout the day as a mid-routine refresh after a workout, after a mask, after sun exposure, or when an active breakout flares. The effects are subtle and cumulative. Within one to two weeks of consistent twice-daily use, people with sensitive-acne overlap typically notice that breakouts settle faster and that the chronic redness around the cheeks and jawline softens. Rosacea-prone users often notice that flushing episodes are shorter. Eczema sufferers report fewer flare-up episodes, particularly when the spray is used as a daily maintenance step.
The limitations are honest and well-known. The price is the most-cited one — $28 for 120ml of what is essentially saltwater feels expensive, and there is no way around that cost criticism. Generic hypochlorous acid sprays exist at lower per-milliliter prices, and if you don't care about the Tower 28 packaging or the brand's design language, those alternatives use the same active ingredient. A 75ml travel size is the cheaper way to test the waters first. The aluminum aerosol nozzle can also leak slightly if the bottle is jostled in transit. And the effect, taken in isolation, is genuinely subtle — this is a foundational maintenance product, not a transformative single-step treatment. People who come in expecting a dramatic acne or eczema cure tend to be underwhelmed, and severe disease still needs prescription therapy in the lead role.
What justifies the recommendation is the breadth of use cases combined with the safety profile. There are very few products that can be sprayed on broken skin, used during pregnancy, used on kids, used on body breakouts, used after retinol, used after laser, used over rosacea, and used on sensitive-acne overlap, all without any reasonable concern about adverse effects. It has no conflicts with anything else in a routine, which is a rarer property than it sounds. The SOS Daily Rescue Facial Spray covers all of those, and the cumulative benefit on inflammation-driven conditions is well-documented in the dermatology literature even if the cosmetic-grade product itself hasn't been the subject of a published clinical trial.
The market has responded accordingly: roughly twenty-eight thousand reviews, a Sephora bestseller slot, an Allure Best of Beauty award, National Eczema Association acceptance, and a persistent second life on dermatology TikTok. It is the product that built Tower 28's reputation, and it is the product that introduced an entire wave of US consumers to a wound-care active they hadn't heard of before. For a sensitive-skin household — especially one with kids, eczema, or a procedure calendar — it is one of the most useful single bottles you can keep on the shelf.
The hero actives that drive this product's performance.
| Ingredient | Function | Evidence |
|---|---|---|
| Hypochlorous Acid (0.012%) | The entire formula. Hypochlorous acid is the same antimicrobial molecule produced by the human immune system to fight infection, used here at the cosmetic concentration that targets C. acnes, S. aureus, and other skin-overgrowth bacteria without disrupting the broader skin microbiome. There are essentially no other ingredients — this is hypochlorous acid in saline water, purposely minimalist. | Not yet assessed |
Electrolyzed Water, Sodium Chloride, Sodium Hypochlorite, Hypochlorous Acid
treatment
AM & PM
Spray onto clean skin and let air dry before the rest of your routine. Can also be misted throughout the day as needed for redness, post-workout flushing, or post-mask irritation.
Immediate cooling and calming on application. Reduction in active breakout severity, redness, and barrier flushing typically visible within 1-2 weeks of consistent twice-daily use.
Hypochlorous acid is one of the most extensively studied antimicrobial molecules in clinical use. It is endogenously produced by neutrophils as part of the innate immune response, and FDA-cleared hypochlorous acid wound-care preparations have been used in burn units, chronic wound clinics, and dermatology offices for decades. A 2018 review in Clinical, Cosmetic and Investigational Dermatology surveyed the dermatologic applications of HOCl and noted documented efficacy against C. acnes, S. aureus, and other relevant skin bacteria, with a strong tolerability profile and no documented allergic contact dermatitis from the active itself. A 2017 study in the Journal of Drugs in Dermatology evaluated topical hypochlorous acid spray in atopic dermatitis patients and reported significant reductions in S. aureus colonization and clinical severity scores over 4 weeks of daily use. Separate clinical work has documented HOCl's utility in post-procedure recovery (e.g., after fractional laser, microneedling, and chemical peels) by reducing infection risk and accelerating barrier recovery without irritation. Mechanistically, HOCl works by oxidizing key bacterial cell components — proteins and lipid membranes — at concentrations that are too low to damage human skin cells, which gives it a wide therapeutic window. The Tower 28 spray is a cosmetic-grade product rather than an FDA-cleared medical device, but the active concentration and saline carrier are consistent with the clinical formulations used in dermatology, and the formulation logic is straightforward. No published trial has tested SOS Daily Rescue Facial Spray specifically.
Dermatologists have used hypochlorous acid in clinical practice for decades, primarily in wound care and as an adjunct in atopic dermatitis management. Most dermatologists frequently recommend HOCl sprays for patients with eczema, sensitive-acne overlap, post-procedure recovery, and inflammatory rosacea, particularly when stronger antimicrobials like benzoyl peroxide or topical antibiotics are not tolerated. This product is widely cited as the consumer-friendly entry point to the ingredient and is often suggested as a daily maintenance step in pediatric atopic dermatitis routines. Dermatologists typically note that HOCl is most useful as a foundational supportive product rather than a primary treatment for severe disease, and that consistent daily use is more important than any single application.
Spray 2-3 times onto cleansed skin, holding the bottle 6-8 inches from the face. Let air dry — do not pat in. Continue with the rest of your skincare routine after the spray has fully absorbed. Can also be used throughout the day as a refresh after workouts, mask use, sun exposure, or breakout flares. Safe for use on broken skin, eczema patches, post-procedure skin, and body breakouts. Pregnancy-safe and gentle enough for children. Replace 12 months after opening per the standard PAO marking.
At $28 for 120ml, the spray is expensive for the ingredient simplicity. A 75ml travel size is also available, and is the better way to test the product before committing to the full bottle. Generic hypochlorous acid sprays from brands like Briotech and SkinSmart deliver the same active at lower per-ml prices, and if cost is the priority, those are valid alternatives. The Tower 28 premium reflects the brand's positioning, the National Eczema Association heritage, and the role this product played in popularizing the ingredient in mainstream US skincare. For users who want the brand integration with the rest of the SOS line, or who specifically value the formulation discipline, the price is defensible. For users primarily interested in the active itself, alternatives at half the cost exist.
Anyone with sensitive, eczema-prone, rosacea-prone, or sensitive-acne overlap skin who wants a foundational antimicrobial maintenance step; people recovering from in-office procedures or barrier damage; pregnant or breastfeeding users seeking safe acne care; parents with kids who have eczema; anyone curious to try cosmetic hypochlorous acid for the first time.
Cost-conscious users who would be equally well served by generic hypochlorous acid sprays from Briotech or SkinSmart; people expecting a dramatic single-step transformation rather than cumulative maintenance benefit; anyone who finds the faint chlorine note bothersome; users with severe acne who need prescription therapy as the primary intervention.
Ready to try Tower 28 SOS Daily Rescue Facial Spray?
Buy at Amazon ♥Watery mist — sprays as a fine even cloud
Faint clean chlorine note
Aluminum aerosol bottle with fine mist nozzle, 120ml (also available in 75ml travel size)
Cooling, weightless mist that absorbs almost immediately. No tingling, no stinging — even on broken or sensitized skin. Within 1-2 weeks of consistent use, visible reduction in surface inflammation around active breakouts and barrier-related redness.
Lasts about 2-3 months when used twice a day
All Year
Amy Liu founded Tower 28 partly because she had severe eczema and could not find color cosmetics that didn't trigger flares. Hypochlorous acid had been used in clinical wound care for decades — derm offices already used it on patients, and Liu's own dermatologist had recommended it to her. She built the SOS Daily Rescue Facial Spray as the consumer-friendly version of that clinical product, and it launched in 2020. The spray is widely credited with introducing hypochlorous acid to mainstream US skincare, and the ingredient has since become a recognized name across sensitive-skin dermatology.
Tower 28 was founded in 2019 by Amy Liu around National Eczema Association acceptance standards. The SOS Daily Rescue Facial Spray is the brand's signature product and the original popularizer of cosmetic hypochlorous acid in the US, which has since become a widely recognized ingredient in sensitive-skin dermatology.
Hypochlorous acid is bleach.
Hypochlorous acid (HOCl) and household bleach (sodium hypochlorite at high concentration) are different molecules with different effects. HOCl is the same molecule the immune system produces to fight infection, and at cosmetic concentrations it is gentle and non-damaging.
If a product is just water and salt, it can't be doing anything.
The active here is the hypochlorous acid generated through electrolysis of saline. The minimalism is real, but the active is a clinically validated antimicrobial used in wound care.
Facial sprays are just expensive water.
Most are. This one is one of the few exceptions — the formulation contains a documented antimicrobial active, not just thermal water with marketing.
It delivers hypochlorous acid — a gentle antimicrobial used in clinical wound care — to the skin. This addresses the bacterial overgrowth involved in acne, eczema flares, post-procedure recovery, and post-workout flushing, without disrupting the broader skin microbiome the way alcohol or benzoyl peroxide does.
Yes. Hypochlorous acid is the same molecule your immune system produces to fight infection, and it has been used in FDA-cleared wound care products for decades. At cosmetic concentrations it is gentle, non-irritating, and safe for daily use even on broken skin.
Yes, but as a supportive product rather than a primary treatment. It reduces the bacterial component of inflammatory acne and calms the surface inflammation around active breakouts. For severe or cystic acne, it works best alongside a prescription treatment plan.
Yes. Spray on clean skin before your retinol — the spray works as a soothing pre-step that reduces the irritation retinoids can cause. It can also be used after retinoid application as a mid-day calming refresh.
Yes. The formula is essentially saline plus hypochlorous acid, which has no pregnancy-cautious ingredients and is gentle enough for use on children. Many parents use it on kids with eczema or post-bug-bite irritation.
The spray is pure hypochlorous acid in saline — minimalist and used as a baseline antimicrobial layer. The Clear Skin Serum, Clay Mask, and Cleanser build on that hypochlorous acid foundation by adding niacinamide, azelaic acid derivatives, and other actives for more complete daily care.
Recurring themes our editors read across retailer reviews of this product — summaries in our words, not quotations, and not a substitute for your own patch test.
Calms breakouts overnight
No sting
Useful for post-workout flushing
Safe for kids
Works on body breakouts
Faint chlorine smell
Pricey for what's essentially saltwater
Spray nozzle can leak
Subtle effect on its own
Verified answers from our questions library — the nuance a product page cannot carry.
