Cymbopogon Flexuosus Oil

Cymbopogon flexuosus (lemongrass) oil is an essential oil used for fragrance and has a high proportion of citral (geranial/neral), a well-documented irritant and contact allergen in patch testing, with irritation risk increasing as concentration and leave-on exposure rise. Even at the low levels typically used in cosmetics (often <1% in leave-on products, higher in rinse-off), it can trigger stinging, erythema, and eczema flares in sensitive or barrier-impaired skin, with both immediate irritancy and delayed sensitization concerns. Given its frequent association with fragrance allergy and the heightened vulnerability of eczema-prone patients, it warrants a high irritancy score for patient safety. Safety Notes: Cymbopogon flexuosus (lemongrass) oil is a fragrance/essential oil used at trace levels in mass-market moisturizers, toners, and cleansers (often ~0.0005–0.05%) to meet IFRA-related allergen management and minimize irritation in leave-on products. In rinse-off soaps/body washes and in consumer-available aromatherapy-style oils, balms, and spot-use blends, it is commonly formulated around 0.5–2% and can reach about 5% in high-fragrance OTC products; above this is uncommon for general skincare due to sensitization risk and fragrance compliance constraints.