Mandelic Acid

An alpha-hydroxy acid (AHA) derived from bitter almonds with a larger molecular structure than glycolic acid, resulting in slower and more superficial penetration. This makes it better tolerated on sensitive or reactive skin and significantly less likely to cause post-inflammatory hyperpigmentation — making it the preferred AHA for medium-to-deep skin tones where glycolic acid can trigger PIH rather than fade it. Evidence base is thinner than glycolic acid (fewer large RCTs), but clinical results for mild photoaging, acne, and uneven tone are well-documented in practice and smaller studies.