BHA; beta hydroxy acid.
Exfoliant, keratolytic support, acne-prone skin care active.
Cleansers, toners, serums, spot products, shampoos.
Product type, percentage, pH context, leave-on exposure, dryness history, and other exfoliants.
Common role
Salicylic acid can appear in rinse-off cleansers, leave-on exfoliants, spot products, and scalp products. The same ingredient name does not mean the same exposure.
How to read it
Check whether the product is rinse-off or leave-on, whether a percentage is disclosed, and whether the routine already includes acids, retinoids, or drying treatments.
Context
Dry, sensitive, barrier-compromised, or recently treated skin may need a slower introduction. Scalp and face products also have different use contexts.
Limits
The label cannot show pH, free acid availability, or your tolerance. Treat it as a structured review item, not a standalone decision.
Practical reader checklist
Use this ingredient page as a sequence, not as a score. First confirm the product type and area of use. Then look at where the ingredient appears, which function group it belongs to, and whether nearby ingredients change the likely role. Finally, compare the label with your own routine: frequency, layering, climate, cleansing step, and any repeated reactions.
| Question | Why it matters | Useful next step |
|---|---|---|
| Is the product rinse-off or leave-on? | Contact time changes how much the ingredient matters. | Read category guides before making a preference rule. |
| Is this a base ingredient or a claim ingredient? | Some names mainly shape texture, while others support a front-label claim. | Check surrounding humectants, emollients, preservatives, fragrance, and actives. |
| Have I reacted to a similar formula before? | Personal history is more useful than a universal rating. | Record the full product and routine, not only one ingredient. |
What this page cannot tell you
No ingredient dossier can show exact concentration, raw material grade, processing method, finished-product stability, packaging compatibility, preservative challenge testing, or your own tolerance. Treat the dossier as a way to narrow the next check, then return to the original label and current product version.
After reading the method, open the iOS app to review product records, ingredient tables, source notes, and personal preference profiles.