COSRX The 6 Peptide Skin Booster Serum(150ml)

1. Use after cleansing as a toner before ampoule, serum or moisturizer.
2. Dispense a few drops and pat gently over the face.
3. Follow with serum and moisturizer.

Benefits

• Firms and improves elasticity with 6-peptide complex
  
• Visibly lifts and tightens sagging skin
  
• Smooths rough texture and refines pores
  
• Brightens and evens skin tone
  
• Boosts radiance and overall skin vitality
  
• Lightweight, toner-like texture absorbs quickly
  
• Clinically tested for sensitive and acne-prone skin
  
• Non-comedogenic and hypoallergenic

Suitable for all skin types, especially those with complex skin concerns.

Water, Dipropylene Glycol, Glycerin, Pentylene Glycol, 1,2-Hexanediol, Niacinamide, Ammonium Acryloyldimethyltaurate/VP Copolymer, Polyacrylate Crosspolymer-6, Butylene Glycol, Xanthan Gum, Ethylhexylglycerin, Adenosine, Polyquaternium-51, Disodium EDTA, Citric Acid, Caprylyl Glycol, Betaine, t-Butyl Alcohol, Sodium PCA, Sodium Lactate, Acetyl Hexapeptide-8, Copper Tripeptide-1, PCA, sh-Polypeptide-121, Serine, Alanine, Allantoin, Sodium Hyaluronate, Acetyl Glucosamine, Glycine, Glutamic Acid, Lysine HCl, Threonine, Dipeptide Diaminobutyroyl Benzylamide Diacetate, Arginine, Tocopherol, Oligopeptide-68, Proline, Dextran, Palmitoyl Tripeptide-8, Glycine Soja (Soybean) Oil, Hydrogenated Lecithin, Potassium Sorbate, Sodium Oleate

What exactly is a peptide, and why does my skin need six of them?
Peptides are short chains of amino acids — essentially the building blocks of proteins like collagen and elastin. Different peptides signal the skin to perform different functions: some encourage collagen production, others relax wrinkle-forming muscle contractions, and others brighten or soothe. Most serums include one or two peptides as supporting ingredients. This formula is built around six, each chosen for a distinct clinical function.

Is this suitable for sensitive skin?
Yes. This serum has been clinically tested for sensitive skin irritation and hypoallergenic tolerance. The inclusion of Allantoin and Palmitoyl Tripeptide-8 (an anti-inflammatory peptide) means it actively works to calm skin rather than challenge it. As always, a patch test is recommended if your skin is particularly reactive.

Can I use this alongside prescription skincare like tretinoin or other actives?
Peptides are generally compatible with most actives, including retinoids, vitamin C, and AHAs/BHAs. However, some research suggests very low pH environments (from high-strength vitamin C or acid exfoliants) can reduce peptide efficacy. To be safe, apply the booster first on a cleansed face, then layer your other actives on top — or alternate timing between morning and evening use.

How soon will I see results?
Skin texture and hydration improvements are often noticeable within 1–2 weeks of consistent use. More significant changes in firmness, fine lines, and tone typically become visible from 4–8 weeks onward. Peptides are not overnight miracle workers — they're long-game players that rebuild your skin's architecture gradually and sustainably.