Five years ago, if you asked a dermatologist about hypochlorous acid, you got a nod and a mention of wound care clinics. Ask one today, and there is a reasonable chance they will tell you to spray this on your face after your workout. That shift — hypochlorous acid as a clinical curiosity to hypochlorous acid as a mainstream skincare step — happened almost entirely because of this one product. The SOS Daily Rescue Spray did not invent the chemistry, and it was not the first HOCl product on a shelf, but it was the first one that combined a stable formulation, an actually pleasant mister, and enough marketing savvy to put the active in front of people who had never heard of it. Everything else in the category that came after is chasing this bottle.
Amy Liu founded Tower 28 in 2019 specifically because her daughter's severe eczema had left her unable to find products she could use without triggering a flare. The SOS line grew out of the observation that hypochlorous acid — long used in hospital wound irrigation and ophthalmology — was nearly impossible to find as a stable, consumer-friendly product. The version she launched was essentially a medical technology in a pretty bottle, and the bet paid off: the spray has accumulated three separate dermatology-organization seals (National Eczema, National Psoriasis, National Rosacea), thousands of overwhelmingly positive Sephora reviews, and the kind of word-of-mouth that makes it show up in dermatology waiting rooms nationwide.
The experience of using it is almost anticlimactic in the best way. You hold the bottle about six inches from your face, pump the mister, and a very fine veil of water settles across your skin. There is a faint pool-chlorine note for the first two seconds — entirely the chemistry of the active, not an added scent — and then it is gone. Within thirty seconds the mist has absorbed with zero residue. If your skin was flushed or stinging when you started, it usually is not by the time you reach for your next product. If it was not, you will not notice much, because this spray is not doing anything visual on healthy skin. It is a quiet, corrective tool that reveals its value when things go wrong.
And things go wrong in a lot of ways. The spray shines for people dealing with the full menu of reactive skin situations: post-gym breakout prevention by reducing surface bacteria on sweat-prone zones, rosacea flare management, eczema calming during an active patch, post-procedure recovery after a peel or laser, and the general 'my face is angry and I don't know why' situation that hits most adult skin occasionally. It is pregnancy-safe, breastfeeding-safe, and gentle enough that parents use it on children with eczema. The tolerability ceiling is so high that it is genuinely difficult to find a skin scenario where this spray is contraindicated.
Its weak points are worth naming. It provides no hydration despite being wet, no barrier repair, no brightening, no exfoliation — nothing that most people associate with the word 'treatment.' It is a calming and antimicrobial step, full stop, and needs to be paired with a real moisturizer to finish the job. The formula is also photosensitive — the opaque bottle is not a design choice but a stability requirement — and you have to finish an opened bottle within six months before the HOCl slowly reverts to glorified saltwater. And the price, while not absurd, runs meaningfully higher than medical-grade HOCl sprays from wound-care suppliers, which will do the core antimicrobial job for a fraction of the cost.
What you are paying for in the Tower 28 version is the stabilization engineering, the fine-mist dispenser that actually delivers a facial mist rather than a water squirt, and the brand's willingness to put the product through three separate dermatology-nonprofit validation processes. Those seals are not marketing decoration — they require ingredient review and real-world testing on the relevant patient population. For someone managing rosacea or eczema, that validation is load-bearing. For someone who just wants to mist their face after a run, it is legitimately worth asking whether a generic HOCl spray from a medical supplier would do the same job for less.
It's also worth noting the sizing options. The 4 oz bottle is the most popular, but Tower 28 sells a 1 oz travel-size version and — critically — a 16 oz refill that drops the per-ounce price meaningfully. If you use this daily, the refill is the version to buy. If you want to test the waters, the travel size is the most affordable entry point into the line.
The bottom line: this is the best version of a category it essentially created. For reactive skin, post-procedure recovery, acne-prone skin that breaks out after workouts, or anyone coming off a course of tretinoin who needs a buffer, the spray earns its shelf space and then some. For someone with resilient, cooperative skin who wants their skincare spending to do more structural work, this is not the place to start — but it is still a nice thing to have in the cabinet for the days when things go sideways.
