Sulfur-Nol – (5) 8% Sulfur and 2% Resorcinol. Extremely aggressive. Preffered to use only on affected areas. Resorcinol works by breaking down hard skin. For acne, this means less clogged pores, and faster skin growth. It reacts with the skin in such a way that it makes it dry, and peel. This works on acne by drying out the sebum, and therefore, stopping the bacterial growth.