Salicylic Acid (BHA)
INCI: Salicylic Acid
Salicylic acid is an oil-soluble acid, which means it can get inside a clogged, oily pore in a way water-soluble acids can't. That makes it the standard choice for blackheads, whiteheads, and oily-skin breakouts — but it does thin the skin's outer layer, so sun protection the next morning isn't optional.
How to introduce it
3x
Starting / week
7x
Target / week
4w
Ramp period
8w
Fair to judge by
Possible purging window: weeks 1–4 — temporary increased breakouts as turnover speeds up. Don't stop or judge the ingredient during this window.
Rules that don't bend
- Patch test 48 hours before first facial use.
- Sunscreen is mandatory every morning a BHA was used the night before.
- Never combine with retinoids in the same session — alternate nights instead.
- Do not apply to broken, sunburned, or actively irritated skin.
Stop and back off if
- — Stinging past 60 seconds.
- — Persistent dryness or flaking despite moisturizing.
Don't combine with
Same-night use can irritate skin or cancel out the active — alternate nights instead of layering them together.