After a few weeks of using this my skin is very clear and my dark spots have completely vanished. It’s felt very gentle on the skin and I personally had no adverse reactions or purging, but I have been using niacinamide for a long time. I put this on before my night cream and wake up to much brighter and soft skin in the morning! 

I've been using the COSRX THE NIACINAMIDE 15 SERUM for a few months now, and I'm absolutely loving it! As someone who struggles with acne-prone skin, I've found that this serum has really helped to clear up my complexion. The niacinamide has helped to reduce inflammation and prevent breakouts, leaving my skin looking smoother and more even-toned. I also appreciate that it's lightweight and non-greasy, making it perfect for daily use. Highly recommend!"

This is the best Niacinamide I have ever used, keeps my face smooth, at first use.  Definitely recommend this. 

K-Beauty all the way. This felt lovely on my skin. I like to apply it after my hyaluronic acid and before my vitamin c in the morning and vitamin a at night. It sinks into my skin beautifully. It would be helpful if I knew the percentage of the niacinimide like Paula’s Choice does.

The best niacinamide product I have tried - the texture is really nice 

I have quite tricky skin, with patches of rosacea post menopause, large pores and  redness. I have tried quite a few niacinamide products but this easily the best with pretty rapid results. I can disguise the redness/pores quite well with mineral foundation but liquid foundation splits after a few hours. However, I’ve only used this for a few days and the difference is amazing, flakiness gone, skin texture improved, redness reduced, pores less visible and liquid foundation looking smoother and more even. It seems to have a cool feel on the skin too which is great for inflammation and irritation- will be a perennial product in my skin care routine.