Nioxin Scalp Treatment 1 is a leave in treatment for fine, natural, normal to thin-looking hair. Nioxin Scalp Treatment 1 is a daily leave-in scalp treatment that delivers essential botanicals, nutrients, antioxidants & vitamins onto the scalp & hair to help safeguard against residues & DHT buildup on the scalp. May cause temporary redness after application. Bio Amp adds thickness & strength whilst Activ-Renewal gives a more youthful-looking scalp & fuller, healthier looking hair. Transactive Delivery System delivers essential nutrients onto the scalp which improves the appearance of thinning hair & creates an environment for fuller, healthier looking hair