Lawsonia Inermis Flower/Fruit/Leaf Extract

Lawsonia inermis (henna) extract is used as a botanical dye/conditioning extract in hair and skin products, typically at low-to-moderate levels, but it contains lawsone and other plant constituents that can provoke irritation and allergic contact dermatitis in a subset of users. Patch-test data and clinical case reports document sensitization reactions (especially in individuals with eczema or compromised barriers), and “henna” exposures are a recognized trigger even when marketed as gentle. Given the meaningful risk to highly sensitive skin and the possibility of delayed sensitization, a moderate irritancy score is warranted and patch testing is prudent. Safety Notes: In mainstream skincare, Lawsonia inermis (henna) flower/fruit/leaf extract is most often used as a minor botanical/antioxidant component in multi-extract blends, where finished-product use levels can be as low as ~0.0005–0.05%. Higher levels are seen in consumer-available “henna/herbal” masks, hair/scalp, and tinted or botanical color-adjacent formulations where the extract (not raw powder) is intentionally featured, typically ~1–5% depending on extract strength and sensory/color constraints; levels above this are uncommon in standard OTC skincare due to staining potential and formula aesthetics, especially in leave-on products.