Unlock the secret to thicker, fuller hair with Nioxin Diaboost Hair Thickening Serum, proven to instantly boost hair diameter and protects hair against breakage, allowing it to grow longer* (with daily use). Our advanced formula is specifically designed to boost hair thickness and density, giving you thicker, fuller-looking hair instantly.** This powerful treatment not only enhances the thickness of your hair but also strengthens and nourishes it from within, leaving it more manageable. With ingredients like caffeine and niacinamide, Diaboost thickens the hair at the roots whilst also protecting against hair breakage. Try this hair thickening treatment daily alongside your Nioxin Scalp+ Hair Thickening System for optimal results. *Nioxin Money Back Guarantee is applicable on selected Nioxin products. ** vs non-conditioning shampoo