NIOXIN Scalp + Hair Thickening Leave-In Treatment System 1 — 6.8 fl oz, Lightweight Scalp-Nourishing Formula for Natural Hair

Nioxin Scalp + Hair Thickening System 1 Leave-On Treatment is a salon-formulated leave-in that helps improve hair thickness appearance and nourishes the scalp for natural or untreated hair with light thinning.

This lightweight leave-on treatment is the finishing step in Nioxin’s System 1 routine, engineered to refresh the scalp, add texture and increase the fullness of each hair strand. Formulated with antioxidants, botanicals and Nioxin’s Transactive Delivery System 2.0 technology, it targets scalp health while helping hair look thicker and more resilient without weighing strands down.

How does this treatment make hair look thicker?

The formula works at the strand and scalp level to increase diameter and amplify texture, creating the visual impression of denser hair. It coats hair fibers and supports fuller-looking strands while helping reduce breakage that can make hair appear sparse.

• Transactive Delivery System 2.0 to help deliver ingredients to the scalp and hair fiber
• Ingredients that add body to each strand for more visible thickness
• Lightweight, non-greasy finish that preserves style volume

Will this support a healthier scalp environment?

This leave-in complements the System 1 regimen by nourishing the scalp with botanicals and antioxidants that help maintain balance and comfort. It helps clear residues that can interfere with scalp condition, creating a cleaner foundation for stronger-looking hair.

• Antioxidant-rich botanicals to soothe and condition scalp skin
• Formulation designed to help remove excess sebum when used with the full system
• Non-heavy application that leaves the scalp feeling refreshed

How do I use the leave-on treatment in my routine?

Use the leave-on treatment as the final step after cleansing and conditioning with System 1 products. Apply to towel-dried or dry hair at the scalp and distribute through lengths as needed; do not rinse out. Styling can follow as usual.

• Apply a few sprays or pumps directly to the scalp across problem areas
• Gently massage to distribute, then comb through for even coverage
• Use daily or as recommended by your stylist for best visible results

What results can I expect and when?

Visible improvements in texture and volume are typically noticed within weeks when used consistently as part of the three-step System 1 program. Many users report fuller-looking hair and reduced appearance of thinning with continued use over time.

• Often visible increase in hair fullness within about 30 days when combined with System 1
• Helps protect against breakage that can make hair appear thinner
• Provides a healthy-looking shine without weighing hair down

Who is this for: Nioxin System 1 Scalp + Hair Thickening Leave-On Treatment is designed for people with natural or untreated hair who are experiencing light thinning and want to boost visible fullness while caring for scalp condition. It’s suitable for daily use and integrates into a professional three-step regimen for those seeking salon-grade support without heavy styling products.

Ingredients

WATER/EAU, NIACINAMIDE, CAFFEINE, PHENOXYETHANOL, SODIUM BENZOATE, BENZYL ALCOHOL, ACRYLATES/C10-30 ALKYL ACRYLATE CROSSPOLYMER, POLYSORBATE 60, POLYSORBATE 80, ACETAMIDE MEA, TRIETHANOLAMINE, PROPYLENE GLYCOL, PEG-23M, TETRASODIUM EDTA, METHYL NICOTINATE, FRAGRANCE/PARFUM, PEG-30 DIPOLYHYDROXYSTEARATE, MENTHA PIPERITA (PEPPERMINT) OIL, MENTHA ARVENSIS LEAF OIL, MENTHOL, TRIDECETH-6, CAMELLIA SINENSIS LEAF EXTRACT, LIMONENE, SILICA, CYSTINE BIS-PG-PROPYL SILANETRIOL, BIOTIN, LECITHIN, TOCOPHERYL ACETATE, CITRUS PARADISI (GRAPEFRUIT) PEEL EXTRACT, HUMULUS LUPULUS (HOPS) FLOWER EXTRACT, URTICA DIOICA (NETTLE) LEAF EXTRACT, YEAST EXTRACT/EXTRAIT DE LEVURE, ACER SACCHARUM (SUGAR MAPLE) EXTRACT, CITRUS LIMON (LEMON) PEEL EXTRACT, SACCHARUM OFFICINARUM EXTRACT, VACCINIUM MYRTILLUS LEAF EXTRACT, CITRUS AURANTIUM DULCIS (ORANGE) FRUIT EXTRACT, POTASSIUM SORBATE.