Nioxin Anti-Hairloss Serum is a thickening leave-in treatment for thinning hair. The serum is made with a clinically proven formula consisting of sandalwood, lauric acid and caffeine which work together to improve hair anchoring, reduce hair loss and give visibly thicker and stronger hair from the first application. Anti-Hairloss Serum is enriched with innovative and nourishing ingredients that help support healthy hair growth and prevent common causes of thinning hair. Clinically and dermatologically tested. Use with Anti-Hairloss shampoo and Night Denisty Rescue for best results.