Achieve fuller-looking lengths with the Nioxin System 2 Scalp and Hair Thickening Treatment. The powerful serum works to protect against damage and breakage for a stronger-feeling finish. Designed to deliver visible results in 30 days, the formula is enriched with niacinamide and biotin to help fortify strands. When used with the System 2 Shampoo and Conditioner as part of a three-step regimen, the treatment promotes a thicker, healthier appearance. Dermatologist tested.