La Roche-Posay Effaclar Ultra Concentrated Anti-imperfection Serum With Salicylic Acid & Niacinamide For Oily & Acne Prone Skin is a powerful blend of exfoliating acids and soothing niacinamide that specifically targets blackheads, pimples, marks, and visible pores. This unique formula does not need to be rinsed off, leaving the skin feeling refined and purified. This serum strikes the perfect balance between exfoliation and calming effects, working to unclog pores and correct stubborn imperfections and marks over time.This groundbreaking La Roche-Posay product is the first of its kind to combine such a high concentration of synergistic active ingredients. It contains 3 keratolytic acids to minimize imperfections and marks, along with niacinamide and Thermal spring water to soothe and reduce redness. The Tri-acid complex includes 1.5% salicylic acid, 3.5% glycolic acid, and 0.45% LHA. Salicylic acid deeply cleanses pores and prevents excess sebum production, while glycolic acid promotes skin renewal for a more radiant complexion and targets marks. LHA gently exfoliates the skin and refines pores for a smoother texture.Niacinamide, also known as vitamin B3, strengthens the skin barrier, provides intense soothing properties, and reduces skin irritations. It also aids in minimizing pores and brightening dark spots for a more even complexion.