The Derma Co. 2% Salicylic Acid Serum is oil-soluble, which allows it to easily penetrate deep within pores and clear sebum clogs that also cause acne. The addition of witch hazel and willow bark in this serum soothes and prevents moisture loss during exfoliation. Dermatologically tested, this 2% salicylic acid serum is safe to use for anyone with acne, open pores, excess sebum production, blackheads and whiteheads.