Hypochlorous acid spray: TikTok miracle or actually useful?

Every skincare account I follow is spraying hypochlorous acid on their face after the gym, before makeup, on their pillow. Some sell it for 30 euros a bottle. Is there anything to it?

There is something to it, and also a lot of marketing. Nurse's view:

Hypochlorous acid (HOCl) is what your own white blood cells make to kill microbes. Diluted, it has been used for years in wound care and as an eyelid cleanser because it is antimicrobial and very gentle: no sting, no drying, safe around the eyes.

What that means for your face:

• After the gym, after sweating, after hair removal, on irritated skin: yes, it is a sensible, gentle way to clean without stripping. That is its best use.
• For acne: modest at best. It can calm things down, but it does not replace benzoyl peroxide, adapalene or whatever your dermatologist prescribed.
• As a moisturiser or "barrier repair": no. It is water with a bit of active chlorine in it; it does nothing for hydration.

Buying it: the concentration you want is around 0.01 to 0.02%. It is not stable forever; buy an opaque bottle, keep it out of the sun and use it within a few months of opening. A pharmacy brand at 8 euros is the same molecule as the influencer brand at 30.

Can confirm the gym use. I keep a small bottle in the bag, spray after training when I cannot shower straight away, and the forehead breakouts I used to get from the cap are gone. Nothing magical, just clean skin.