Nioxin Pro Clinical's Hair Fall Defence Serum is a leave-on scalp treatment for thinning hair. Designed for daily use, it's clinically proven to increase hair anchorage with visible results in only 8 weeks* while thickening hair from the very first use. It's formulated with innovative ingredients including SANDALORE™, caffeine, lauric acid, and niacinamide. Together they work to stimulate and nourish the hair follicles to prolong the growth cycle and improve hair resistance for fuller-looking hair.