What’s in OBAGI NU-CILTM Eyebrow Boosting Serum? 💭 Biotin: supports keratin production leading to thicker, fuller-looking eyebrows Proprietary Lipid Compound: targets the anagen phase of the brow hair, leading to appearance of darker and fuller-looking eyebrows Sodium Hyaluronate: seals in moisture, leading to more voluminous looking eyebrows Panthenol: helps with hair conditioning, moisture, and texture improvement