NIOXIN System 4 Shampoo & Conditioner Liter Duo — Color-Treated Thinning Hair, Pumps Included

NIOXIN System 4 Liter Duo is a two-step professional shampoo and conditioner set with pumps, formulated to cleanse, strengthen and help visibly thicken dry, damaged, color-treated hair experiencing progressed thinning.

Designed as the first two steps of NIOXIN’s three-part regimen, this liter-size duo pairs a derma-purifying Cleanser with a lightweight Scalp Therapy Conditioner to create a healthier scalp environment and add density-looking results. The formulas use targeted technologies — Pro-Color Shield in the cleanser to remove buildup while protecting pigment, and AMP technology in the conditioner to help retain moisture balance and resilience — making the set suitable for salon use or at-home maintenance when you need larger sizes and pumps for easy dispensing.

How does the NIOXIN System 4 shampoo help color-treated hair?

The cleanser is engineered to remove sebum, pollutants and product residue that can weigh hair down and mute color vibrancy. It focuses on scalp purity so strands can sit fuller and reflect color better without harsh stripping.

• Pro-Color Shield helps protect hair pigment during cleansing
• Deeply removes excess sebum and environmental buildup
• Formulated for dry, damaged, color-treated hair with progressed thinning

What benefits does the Scalp Therapy Conditioner provide?

The conditioner is lightweight but nourishing, designed to strengthen hair and improve manageability without flattening the roots. AMP technology works to help retain moisture and increase resilience, leaving hair looking fuller and softer to the touch.

• Adds moisture balance without heavy residue
• Strengthens and reduces the appearance of breakage
• Supports thicker, fuller-looking hair when used as part of the system

How quickly will I notice thicker-looking hair?

Results vary by individual, but the System 4 regimen is clinically designed to show visible density and fullness improvements when used consistently. Users often report improved texture and a fuller appearance within weeks of regular use.

• Clinically tested formulation aimed at visible improvement in about 30 days
• Targets both scalp environment and strand structure for combined effect
• Best used as part of the three-step NIOXIN protocol for maximum benefit

How should I use the liter duo for best results?

Use the Cleanser first to remove buildup, rinse thoroughly, then apply the Scalp Therapy Conditioner focusing on mid-lengths to ends and rinse. For full protocol benefits, follow with the recommended third-step scalp treatment in the NIOXIN System 4 kit.

• Apply shampoo to wet hair, massage into scalp, rinse; repeat if needed
• Work conditioner through lengths, leave briefly then rinse fully
• Use daily or as directed, and pair with the System 4 scalp treatment for optimal results

Who is this for: NIOXIN System 4 Liter Duo is intended for people with dry, damaged, color-treated hair experiencing progressed thinning who want salon-sized bottles with pumps for easy daily use. It suits anyone seeking a gentle, targeted approach to improve scalp clarity and the appearance of hair density without sacrificing color protection.

Ingredients

Shampoo: WATER/EAU, SODIUM LAURETH SULFATE, SODIUM LAURYL SULFATE, CITRIC ACID, SODIUM CHLORIDE, PPG-2 HYDROXYETHYL COCO/ISOSTEARAMIDE, SODIUM CITRATE, SODIUM XYLENESULFONATE, SODIUM BENZOATE, SALICYLIC ACID, SODIUM HYDROXIDE, TETRASODIUM EDTA, MENTHA PIPERITA (PEPPERMINT) OIL, MENTHA ARVENSIS LEAF OIL, MENTHOL, TRISODIUM ETHYLENEDIAMINE DISUCCINATE, METHYLPARABEN, POLYQUATERNIUM-10, PROPYLENE GLYCOL, CAMELLIA SINENSIS LEAF EXTRACT, CYSTINE BIS-PG-PROPYL SILANETRIOL, BIOTIN, LECITHIN, NIACINAMIDE, PANTHENOL, TOCOPHERYL ACETATE, FOENICULUM VULGARE (FENNEL) FRUIT EXTRACT, SODIUM ACETATE, ISOPROPYL ALCOHOL, YELLOW 5, YEAST EXTRACT/ EXTRAIT DE LEVURE, ACER SACCHARUM (SUGAR MAPLE) EXTRACT, CITRUS LIMON (LEMON) PEEL EXTRACT, SACCHARUM OFFICINARUM EXTRACT, VACCINIUM MYRTILLUS LEAF EXTRACT, BLUE 1, CITRUS AURANTIUM DULCIS (ORANGE) FRUIT EXTRACT, RED 33, POTASSIUM SORBATE. Conditioner: Aqua/Water/Eau, Cetyl Alcohol, Stearamidopropyl Dimethylamine, Stearyl Alcohol, Quaternium-18, Phenoxyethanol, Benzyl Alcohol, Cetearyl Alcohol, Hydroxypropyl Guar, Glyceryl Stearate, Oleyl Alcohol, Propylparaben, Polysorbate 60, Mentha Piperita (Peppermint) Oil, Mentha Arvensis Leaf Oil, Menthol, Propylene Glycol, Methylparaben, EDTA, Hydroxyethylcellulose, Citric Acid, Camellia Sinensis Leaf Extract, Quaternium-80, Cystine Bis-PG-Propyl Silanetriol, Biotin, Lecithin, Niacinamide, Panthenol, Tocopheryl Acetate, Foeniculum Vulgare (Fennel) Fruit Extract, Acer Saccharum (Sugar Maple) Extract, Citrus Limon (Lemon) Peel Extract, Saccharum Officinarum/Sugar Cane Extract/Extrait de canne à sucre, Vaccinium Myrtillus Leaf Extract, Faex Extract/Yeast Extract/Extrait de levure, Citrus Aurantium Dulcis (Orange) Fruit Extract, Maltodextrin, Blue 1 (CI 42090), Potassium Sorbate, Sodium Benzoate, Ethylparaben, Butylparaben