La Roche-Posay Effaclar Ultra Concentrated Anti-imperfection Serum With Salicylic Acid & Niacinamide For Oily & Acne Prone Skin is a concentrate of exfoliating acids combined with soothing niacinamide, that targets blackheads, pimples, marks and visible pores. This no-rinse formula leaves the skin refined and purified. Perfect balance between peeling and soothing actions, the serum unclogs pores and corrects persistent imperfections and marks day after day. The first ultra sensorial La Roche-Posay care to combine such a high concentration of synergic actives: 3 keratolytic acids to reduce imperfections and marks + niacinamide & Thermal spring water for a soothing and anti-redness effect. Tri-acid complex contains salicylic acid 1.5%, glycolic acid 3.5% and LHA 0.45%. Salicylic acid deeply unclogs pores and prevents sebum accumulation. Glycolic acid activates skin renewal for improved skin radiance, with high efficacy on marks. LHA gently micro-exfoliates the skin and refines pores. Niacinamide, also known as [vitamin B3], improves the skin barrier, intensely soothes and decreases skin irritations. It also helps reducing skin pores and brightening dark spots.