The Ingredient: Benzoyl peroxide
The Product: La Roche-Posay Effaclar Medicated Gel Cleanser ($15)
Another oldie but a goodie, benzoyl peroxide is an alpha hydroxy acid that's a stone-cold killer. "Benzoyl peroxide is one of the oldest acne medications, used for its ability to literally kill everything," Dr. Friedman explained. Part of that everything is the p. acnes bacteria, which is what feeds on your clogged-up pore gunk, multiplies, and causes your skin to go haywire. Since benzoyl peroxide focuses on destroying the bacteria rather than the dead skin cells, it also treats red, swollen pimples in addition to blackheads and whiteheads.
Dr. Friedman warns that while BP is great at mitigating some of the key causes of acne, you also run the risk of it hurting the skin. "At higher concentrations, it can be very irritating because you start to cause damage to skin cells as well," he noted. He's not a huge fan of leave-on products with benzoyl peroxide: "Many consumers use it the wrong way, causing more harm than good."
Instead, he recommends grabbing it in cleanser form, preferably with a concentration that's less than three percent. Which makes this two percent medicated gel cleanser the ideal way to terminate bacteria. The addition of micro-exfoliating acids targets oily patches, allowing it to banish buildup and clear the way for smooth, fresh skin.
