KÉRASTASE Première Hair Repair Serum for Damaged Hair — Lightweight Leave-In, Heat Protection to 450°F

KÉRASTASE Première Hair Repair Serum is a lightweight leave-in treatment that repairs weakened strands, shields hair from heat up to 450°F, and smooths frizz for visibly stronger, shinier hair.

This advanced serum combines peptide technology and glycine to reconnect broken keratin links and reinforce hair fiber integrity without weighing hair down. Designed for use after washing on towel-dried hair, the formula leaves strands easier to detangle, reduces the look of split ends, and creates a protective barrier against humidity and styling heat. The result is hair that feels more resilient, appears glossier, and behaves predictably when you dry and style.

How does this serum repair and strengthen damaged hair?

The serum uses peptides to fortify each strand from the outside while glycine works to rebuild connections within the hair’s keratin structure. Together they reduce breakage and help hair resist mechanical and thermal stress. Because the formula is lightweight and leave-in, it delivers continuous support between washes without buildup.

• Peptides reinforce and smooth the surface of the hair shaft.
• Glycine helps reconnect weakened keratin links inside the fiber.
• Leave-in texture provides ongoing protection and conditioning.
• Visible reduction in split-end appearance and improved strand strength.

Will this product protect my hair during heat styling?

Yes — the serum is formulated to shield hair from heat exposure up to 450°F, making it suitable for most blow-dryers and heat tools. It forms a protective layer that helps minimize thermal damage while smoothing the cuticle for easier styling. Apply before blow-drying for best protection and manageability.

• Heat protection rated up to 450°F for styling tools.
• Creates a protective film to reduce heat-induced breakage.
• Helps smooth the cuticle to aid faster, more even drying.
• Recommended: apply on towel-dried hair before blow-drying or heat tools.

How does it control frizz and humidity?

The serum repels moisture from the air and seals the hair surface to limit frizz and flyaways in humid conditions. By smoothing the cuticle and adding shine, strands reflect light better and look healthier. The lightweight finish keeps hair touchable rather than stiff or crunchy.

• Humidity-defense that reduces frizz and keeps styles intact.
• Smoothes cuticles to lock out moisture and reduce flyaways.
• Delivers visible shine without heavy residue.
• Leaves hair softer and more manageable throughout the day.

How should I use this serum for best results?

Work a small amount through towel-dried hair from mid-lengths to ends, then leave it in—no rinsing required. Follow with blow-drying or heat styling as desired; the product works continuously between washes to protect and strengthen. Adjust the amount based on hair density and length to avoid over-application.

• Apply to towel-dried hair, concentrating on mid-lengths and ends.
• Do not rinse—leave the serum in while blow-drying or air-drying.
• Use sparingly on fine hair; more product may be needed for thick or long hair.
• Incorporate into regular routine for cumulative strengthening benefits.

Who is this for: KÉRASTASE Première Hair Repair Serum is ideal for people with weakened, chemically processed, heat-styled, or frequently manipulated hair seeking a lightweight leave-in that both repairs and protects. It suits those who want smoother, shinier hair with reduced split-end appearance and reliable heat protection while maintaining a natural, touchable finish.

Ingredients

AQUA / WATER / EAU • ISOPROPYL MYRISTATE • DIMETHICONE • TRIETHANOLAMINE • AMODIMETHICONE • PARFUM / FRAGRANCE • PHENOXYETHANOL • CARBOMER • POLYQUATERNIUM-4 • POTATO STARCH MODIFIED • LIMONENE • HYDROXYPROPYL GUAR • BEHENTRIMONIUM CHLORIDE • HYDROLYZED VEGETABLE PROTEIN PG-PROPYL SILANETRIOL • GLYCINE • TRIDECETH-6 • ISOPROPYL ALCOHOL • LINALOOL • CETRIMONIUM CHLORIDE • CITRAL • COUMARIN • BENZYL SALICYLATE • SODIUM BENZOATE • BENZYL ALCOHOL • CITRONELLOL • ALPHA-ISOMETHYL IONONE • POTASSIUM SORBATE • GERANIOL