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About the Product
A high-strength serum with 15% niacinamide—a vitamin B3 derivative that helps regulate oil, fade dark spots, and refine skin texture. This lightweight, watery formula absorbs quickly without residue, making it easy to layer into your morning or evening routine.
Who is This For?
Suitable for all skin types, but especially helpful if you're dealing with excess oil, visible pores, or post-breakout marks. Works well for anyone wanting a more balanced, even-toned complexion.
Key Benefits
Helps control oil and shine throughout the day
Fades dark spots and post-acne marks over time
Minimizes the look of enlarged pores
Calms irritation and supports skin recovery
Key Ingredients
Niacinamide (15%) — Regulates oil, strengthens the skin barrier, and helps even out skin tone
Zinc PCA — Controls sebum and offers antibacterial support to help keep breakouts in check
N-Acetylglucosamine (NAG) — Boosts niacinamide's brightening effects by helping to reduce excess melanin
FAQs
Q: Can I use Cosrx Niacinamide 15 Serum with vitamin C?
A: It is recommended to use vitamin C and high-concentration niacinamide in separate routines (one in AM, one in PM) rather than layering them together, as combining them may reduce efficacy or cause flushing in some individuals.
Q: Is this serum suitable for sensitive skin?
A: The 15% niacinamide concentration is considered high; those with sensitive skin should patch test first and may want to start with every other day application to assess tolerance.
Q: Can I use this serum around my eyes?
A: Yes, the serum can be applied to the under-eye area to address dark spots, but avoid direct contact with the eyes.
Q: Do I need sunscreen when using this serum?
A: Yes, applying SPF 30 or higher during daytime use is recommended, as niacinamide can increase skin's sensitivity and protecting against UV exposure supports the serum's brightening benefits.
Q: How long until I see results?
A: Most users notice improvements in oil control within 1-2 weeks, while fading dark spots and refining texture typically takes 4-8 weeks of consistent use.
Q: When should I apply this in my skincare routine?
A: Apply after cleansing and toning, but before heavier creams or oils; the lightweight formula absorbs quickly and layers well under moisturizer and sunscreen.
Q: Who should avoid using this serum?
A: Those with known niacinamide sensitivity or anyone currently experiencing compromised skin (severe irritation, open wounds, or active eczema flares) should skip this product or consult a dermatologist first.
How to Use
Cleanse your face thoroughly and pat dry. Apply 2-3 drops of serum onto your fingertips. Gently massage the serum into the skin, starting from the center of the face and working outward. Allow the serum to absorb fully before applying the next product. Follow with moisturizer. For daytime use, apply SPF 30 or higher sunscreen as the final step. Can be applied to the under-eye area; avoid direct contact with eyes.
Very high quality packaging and ingredients. Application is simple, just a dropper. The serum is slightly thicker than the hyaluronic serum, but disappears into the skin and works wonders.
B
Beverly W.
I love the COSRX skin
I love the COSRX skin care product line! My skin is on the drier side but still very sensitive. It's been very difficult to find products that keep my face moisturized without breaking out. So many things, even very expensive and quality products, have petrolatum and shea butter in them. Both of them cause breakouts for me. The Niaacinamide 15 is keeping my skin looking radiant. I have bought sever other products and my skin is moisturized and white heads are vanishing.
S
Sandra M.
Everyday skin need
I love niacinamide serums, I have mature skin, normal to oily (depends on the season) and this serum is excellent. My skin can get red and inflamed easily by the simplest products but my skin loved this. I use it daily and will continue to purchase. I recently had a reaction to the ordinarys products and I learned about Cosrx last month.
M
Madeleine B.
I am astonished at how
I am astonished at how well it works on keeping sebum levels down throughout the course of a busy day on my very sensitive skin.
M
Mila
Niacinamide
I'm excited with this product! I have oil skin and niacinamide really help me to control sebum.
