La Roche Posay Effaclar Ultra Concentrated Serum is a concentrate of exfoliating acids combined with soothing niacinamide, that targets blackheads, pimples, marks and visible pores. It targets blemishes, reduces the appearance of fine lines, wrinkles and marks, tightens pores, and regulates sebum production. It is also suitable for acne-prone skin. It does this with a formula, enriched with salicylic acid, LHA and glycolic acid, that help unclog pores, visibly smooth the skin's surface.