A leave-in scalp serum for thin, flat hair that wants more body
Redken Acidic Grow Full System Scalp Density Serum is a leave-in scalp and hair serum for fine, thin or flat hair that lacks density. Built on the Acidic Grow Full 5% Strength Complex, it combines azelaic acid and caffeine with fermented ingredients (bifida ferment lysate and rice ferment filtrate) and sodium hyaluronate. It helps rebalance the pH of the scalp, adds moisture and leaves hair looking fuller and thicker. It is designed as the care step of the Acidic Grow Full shampoo and conditioner routine.
The texture
A light, watery serum that goes straight onto the scalp and does not weigh fine hair down or leave it greasy. It has a fresh citrus scent.
Who it suits
- Fine, thin or flat hair that lacks density
- Anyone wanting fuller-looking hair at the roots
- Hair that looks sparse
- Users of the Acidic Grow Full shampoo and conditioner
Worth knowing before you buy: The formula contains fragrance and citrus essential oils with allergens such as limonene and linalool, so sensitive scalps may want to patch test first. Results build with regular use, not after one application.
Complete the routine

Acidic Grow Shampoo
The density shampoo of the same system.
Shop →
Acidic Grow Conditioner
A light conditioner that keeps fine hair full.
Shop →Characteristics
- Texture: light serum
- Hair type: fine, thin, flat hair
- Concerns: lack of density, flat roots, thinner-looking hair
- When to apply: daily on the scalp
- Main benefits: rebalances scalp pH, adds moisture, fuller and thicker-looking hair
How to use
Apply to a clean, towel-dried or dry scalp, section by section, then massage gently with the fingertips. Do not rinse. Use daily after the Acidic Grow Full shampoo and conditioner.
Active ingredients
- Azelaic acid: part of the Strength Complex that helps rebalance the scalp
- Caffeine: energises the scalp for fuller-looking hair
- Bifida ferment lysate and rice ferment filtrate: fermented ingredients that care for the scalp
- Sodium hyaluronate: adds moisture
Ingredients
AQUA / WATER/EAU · AZELAIC ACID · BIFIDA FERMENT LYSATE · CAFFEINE · CARVONE · CHLORPHENESIN · CITRAL · CITRIC ACID · CITRUS AURANTIUM BERGAMIA PEEL OIL · CITRUS AURANTIUM PEEL OIL · CITRUS LIMON PEEL OIL · GLYCERIN · HYDROXYETHYLPIPERAZINE ETHANE SULFONIC ACID · LIMONENE · LINALOOL · LINALYL ACETATE · PARFUM / FRAGRANCE · PEG-40 HYDROGENATED CASTOR OIL · PENTYLENE GLYCOL · PHENOXYETHANOL · PINENE · PROPYLENE GLYCOL · SACCHAROMYCES/RICE FERMENT FILTRATE · SODIUM BENZOATE · SODIUM HYALURONATE · TETRASODIUM GLUTAMATE DIACETATE
Formulations are updated by the manufacturer from time to time. Always check the packaging you receive.
Manufacturer information
Brand: Redken
Address: 277 rue Saint-Honoré, 75008 Paris, France
EAN: 3474637325510
