I have used many different hair products without having any reaction, including Phillip B Russian Amber, which contains some essential oils. Therefore, I do not experience that I have sensitive skin or scalp. This is the first product I have reacted to, and the reaction came immediately after use. Plus for the product smelling clean, but the scent is not particularly remarkable. Keratin Hair Mask from the same brand has a better and more perfumed scent for those who want that.