Cosrx The Niacinamide 15 Serum 20ml

Cosrx The Niacinamide 15 Serum is a high-concentration brightening serum with 15% niacinamide (vitamin B3) — one of the most researched and effective brightening ingredients in dermatology. At this concentration, niacinamide targets dark spots, uneven tone, excess sebum production, enlarged pores, and dull skin simultaneously.

Zinc PCA regulates sebum and provides anti-inflammatory benefits. Acetyl glucosamine — a precursor to hyaluronic acid — enhances the brightening effect and boosts hydration. Trehalose protects cells under environmental stress. Allantoin soothes and promotes cell renewal. Pullulan provides a temporary tightening effect for immediate visible results. The minimalist formula contains only what your skin needs.

Why customers love it

• 15% niacinamide — clinical-strength brightening
• Zinc PCA — sebum control and anti-inflammatory
• Acetyl glucosamine — brightening enhancer and HA precursor
• Trehalose — cell-protective antioxidant
• Allantoin — soothing and cell renewal
• Pullulan — temporary tightening for instant results
• Multi-tasking — brightens, refines pores, controls oil
• Minimalist formula — clean, effective ingredients only

Perfect for: dark spots, uneven tone, oily skin, large pores, dull skin, hyperpigmentation, post-acne marks, sebum control.

Niacinamide (15%) — clinical-strength vitamin B3 for brightening, pore-refining, sebum control

Zinc PCA — sebum regulation and anti-inflammatory

Acetyl Glucosamine — brightening enhancer and hyaluronic acid precursor

Trehalose — cell-protective stress shield

Allantoin — soothing and cell renewal

Pullulan — natural polysaccharide for temporary tightening

1. After cleansing and toning, dispense 2-3 drops onto your fingertips.
2. Gently pat and press across your face, focusing on dark spots and pores.
3. Follow with moisturiser.
4. Use morning and evening.
5. Always apply sunscreen in the morning.

Pro tip: 15% is a high concentration — if you're new to niacinamide, start with every other evening and build up to twice daily. Some people experience mild flushing (temporary redness) with high-concentration niacinamide; this is harmless and usually stops after a few uses. Niacinamide pairs excellently with hyaluronic acid (use the Cosrx HA Hydra Power Essence), vitamin C (Cosrx Vitamin C Serum), and retinol. The zinc PCA makes this particularly effective for oily, acne-prone skin — zinc regulates the same sebum pathways that cause breakouts. The 20ml size is intentional — at 2-3 drops per use, this lasts 2-3 months.