@skincaresnack: SERUMS 101: If you have acne-prone, oily/combination skin, try this niacinamide serum from @cosrx_official for total acne care. I found Korean skincare products to be great for sensitive skin - always patch test first though! #corsxreview #corsx #cosrxdermrd #koreanbeautysecret #acneproneskincareproducts #skinfluencerproducts #niacinamideserums #serums101