Acetylated Lanolin

Acetylated lanolin is an emollient/occlusive derived from wool wax, typically used at low-to-moderate percentages to improve barrier feel, but lanolin derivatives have a well-documented history of causing contact allergy and irritation in a meaningful subset of patients—especially those with eczema or impaired barriers. Patch-test data and clinical experience place lanolin and its derivatives among more common moisturizer allergens in dermatitis populations, with reactions that can be delayed and clinically significant despite “gentle” marketing. Given the higher risk in sensitized and atopic individuals and the potential for cumulative exposure in leave-on routines, a moderate irritancy score is warranted and patch testing is advisable. Safety Notes: In commercial formulations acetylated lanolin is often used as a minor emollient/plasticizer in creams, lotions, and color cosmetics at ~0.05–1% (sometimes simply to improve slip and barrier feel). In richer leave-on moisturizers, hand/foot creams, and lip products it commonly appears around 2–10%, and high-occlusivity balms/salves and specialty barrier products marketed to consumers can reach ~15–25% to maximize substantivity and water resistance. It is less common at high levels in rinse-off products, where usage is typically kept lower to avoid deposition/feel issues.

Suitability