What is it? Benzoyl peroxide is one of the most powerful anti-acne medications, designed to simultaneously treat multiple acne-causing factors. Naturally antibacterial and antiseptic, benzoyl peroxide helps to reduce the P. acnes bacteria on the skin that's responsible for causing acne in many people. It also contains exfoliating properties that slough off the top layer of dead skin cells, encouraging normal production of cells. Additionally, benzoyl peroxide has an oxidizing property that dries excess oil and sebum on the skin’s surface.

You'll find it in: A wide variety of skincare products such as cleansers, lotions and topical treatments contain benzoyl peroxide. To combat excess oil and bacteria without drying out the skin, experts recommend beginning with a low concentration of benzoyl peroxide (2-5 percent). If a lower concentration doesn't do the trick, try a concentration up to 10 percent. Higher strengths are available by prescription from a doctor, but most likely won’t be needed.

• Cleansers: For combination skin, choose a cream-based product that contains benzoyl peroxide. Oilier skin should opt for a gel-based or exfoliating cleanser. When applying your cleanser, first wet your face; then massage the cleanser for 10 to 20 seconds. For maximum penetration into the pores, let the cleanser sit for a minute or so. If your skin gets too dry, rinse off the cleanser earlier.
• Topical treatments: Both gel and cream-based topical treatments are available. These can be applied to individual blemishes for spot treatment or to entire acne-prone areas for prevention. Many formulas also contain soothing ingredients like green tea or chamomile to combat any irritation that might occur. After washing your face or taking a shower, the American Academy of Dermatology (AAD) recommends waiting 10 to 15 minutes before applying your acne treatment to prevent irritation.

Our product picks: Start with a gentle cleanser that contains benzoyl peroxide, such as Jan Marine Benzoyl Peroxide Wash 2.5% to effectively clear cellular debris and excess sebum without stripping the skin’s natural moisture.

For spot treatments, MD Formulations Benzoyl Peroxide 10 is a fast-absorbing topical acne treatment that both clears and moisturizes the skin.

What to expect: As with any acne medication, don’t be discouraged if you don’t notice immediate results. Results should be seen in about six to eight weeks, with significant improvement occurring after about four to six months. Because benzoyl peroxide is a particularly strong treatment, you might notice side effects like dryness, irritation, itchiness, peeling or redness when you first start using it. The good news is that as your skin becomes accustomed to the ingredient, you will generally be able to tolerate it better. If irritation doesn’t subside or if you develop a rash, pay a visit to your dermatologist.

Always use sunscreen with at least SPF 15 while using benzoyl peroxide, as it makes your skin more susceptible to sun damage.

Who should avoid it: For those with extremely dry or sensitive skin, it might be wise to avoid this ingredient entirely and opt for something gentler. And if you're using other acne-fighting medications, be sure to talk to your doctor about possible drug interactions. Some medications, like antibiotic lotions, gels or creams like erythromycin, actually help to boost the acne-fighting power of benzoyl peroxide and make it work even better. However, other medications or ingredients may be unsafe to use with benzoyl peroxide, causing painful dryness and other side effects. Your dermatologist can determine what will (and won't!) work with benzoyl peroxide.

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