One of the first lines of defense against pesky pimples, benzoyl peroxide fights acne in two ways. It helps to kill the bacteria that cause acne and acts as a drying agent to soak up the skin's excess oil. But it's also a harsh chemical that can irritate sensitive skin. In most cases, you can stop the irritation by using less and spacing out applications.
Benzoyl peroxide is commonly found in anti-acne creams, face washes and lotions. According to the UN’s Food and Agriculture Organization, it’s also used to bleach flour and cheese whey, cure silicone rubber and manufacture some plastics. The FAO Chemical & Technical Assessment of benzoyl peroxide describes it as a nonwater-soluble crystalline solid created through the reaction of three parent chemicals: benzoyl chloride, hydrogen peroxide and sodium hydroxide.
Benzoyl Peroxide and Skin Care
Benzoyl peroxide can treat acne when it’s used topically. It's especially helpful in reducing P. acnes, the type of bacteria that cause acne, because, unlike some other antibiotic treatments, topical application does not cause bacterial resistance.
Causes of Sensitive Skin
Sensitive skin has no universal cause. But Dr. Leslie Baumann of the American Academy of Dermatology says there are four distinct types of sensitive skin reactions: red, itchy skin caused by allergies or irritants; burning or stinging; acne; and rosacea. Of these, benzoyl peroxide is only used to treat acne. Benzoyl peroxide can cause dryness, according to the National Institutes of Health. But if you end up with extreme itchiness, redness or swelling, see your dermatologist. You might have dermatitis, or you could be experiencing an allergic reaction.
Treating Sensitive Skin With Benzoyl Peroxide
Unless you know the cause of your sensitive skin, proceed cautiously with benzoyl peroxide. The New Zealand Dermatological Society suggests using it every other night initially to see how your skin tolerates it. Also consider the percentage of benzoyl peroxide. The New Zealand Dermatological Society lists three concentration levels: 2.5 percent, 5 percent and 10 percent. If you experience minor redness, dryness or irritation, try a formula with a smaller percentage.
If your skin reacts unfavorably to benzoyl peroxide, there are other ways to treat acne. The American Academy of Dermatology says salicylic acid and retinoids are other possibilities. Summer Rayne of Planet Green suggests looking for treatments with all-natural ingredients such as willow bark and tea tree oil. These ingredients fight bacteria and skin inflammation, she says.