Acne affects an estimated 17 million people in the United States, including 80% to 85% of adolescents and young adults.1-2 While the majority of teenagers with acne would like to speak with their physicians about acne, only about one third actually do.2 Sixty percent of teenagers in this country use OTC products for acne.3 Thus, pharmacists are likely to receive inquiries from adolescents and young adults with acne, as well as parents of teenagers with acne. While only mild cases of acne should be managed with OTC agents, many patients will attempt self-treatment initially with preparations containing benzoyl peroxide or salicylic acid. The purpose of this article is to equip pharmacists with essential information about acne and its treatment, with a focus on the use of nonprescription topical agents.
Acne vulgaris is the most common skin disease and is generally a mild, self-limited skin disease.4 Some cases of acne, however, may be severe and persistent, leaving permanent physical and psychological scars. Pores, or small openings on the skin, typically hold a single hair. At the bottom of each follicle is a group of cells called a sebaceous gland. These glands (also known as pilosebaceous units) produce an oily substance called sebum used to lubricate the hair and skin. Movement of sebum from the sebaceous glands to the skin surface helps to clean out the follicle, carrying away dead skin cells, hair cells, and bacteria. When the follicle becomes clogged and the sebum is trapped inside, acne blemishes (pimples, or ?zits?) develop. Acne pimples can appear as dark-colored follicle plugs (?blackheads?), small white pimples (?whiteheads?), or red, swollen, and painful bumps under the skin.
Acne usually begins during puberty (11-14 years of age), the period when the body increases production of hormones called androgens. Androgens cause sebaceous glands to enlarge and produce more sebum. Mixed with dead skin and hair cells inside the follicle, the excess sebum does not easily make its way out of the follicle, resulting in a plugged follicle. Normal skin-surface bacteria are sometimes trapped inside the clogged follicle. The most common bacterium in acne is Propionibacterium acnes. P acnes is involved in producing the inflammatory response within the pilosebaceous units.5,6 Females may notice that their acne gets worse before each menstrual period. While androgens are the most important hormonal cause of acne,7 other factors such as genetics and certain triggers may be involved in the pathogenesis. These include the use of some cosmetics (skin creams, hair care products), workrelated substances (cooking oils, motor oil), emotional stress, and tight-fitting clothing or sporting equipment (sweatbands, football helmets, chin straps). Medications that can induce or exacerbate acne include oral contraceptives (especially those with a high progestin dose), androgens, danazol, glucocorticoids, lithium, phenytoin, and rifampin.3
For mild cases of acne, gentle cleansing of the affected area twice daily is usually the only necessary treatment. Pharmacists can recommend a gentle soap. Scrubbing the skin should be avoided since it can aggravate the hair follicles. Patients should not pop, squeeze, or pick at pimples, and be instructed to use noncomedogenic cosmetics. Patients should avoid making a habit of unnecessarily touching their face. If known, other exacerbating factors should be minimized. The role of diet in acne is unsubstantiated.8 Patients should be instructed only to avoid foods known to worsen their acne.
OTC Preparations for Acne
The 2 most commonly used, effective ingredients found in OTC products are benzoyl peroxide and salicylic acid. With the exception of mild cases of acne, however, most patients will require prescription-based therapy, either alone or in combination with OTC preparations.9
Benzoyl peroxide exerts its therapeutic effect by releasing free-radical oxygen, which oxidizes bacterial proteins in the sebaceous follicles, decreasing the number of anaerobic bacteria and decreasing irritating-type free fatty acids. Benzoyl peroxide 2.5% to 10% is highly active against P acnes and may also have mild keratolytic properties.2,10 Skin irritation is the most common side effect that occurs at higher concentrations and often attenuates with continued use.2 This may manifest as burning, stinging, redness, peeling, and dryness. Pharmacists should counsel patients to anticipate these side effects even after the first application. Patients should be encouraged to test themselves for skin hypersensitivity or allergy by initially applying benzoyl peroxide to a small area at bedtime only, then slowly increasing the area covered as tolerated up to twice daily.
Pharmacists should not recommend the 10% strength for initial therapy, and should warn patients that these preparations can bleach facial hair and can fade clothing and bedding. Benzoyl peroxide-containing products should not come in contact with the lips, mouth, or other mucous membranes. Patients should be taught not to expect immediate results. Pharmacists should encourage continuous (daily) use of benzoyl peroxide for at least 4 to 6 weeks to assess the effectiveness of treatment. Four to 6 months of treatment may be needed for maximal results.
A wide variety of preparations containing benzoyl peroxide are commercially available (Table). Pharmacists can assist patients in selecting a product with an appropriate vehicle. For example, patients with dry or sensitive skin may benefit more from a cream, and those with oily skin may prefer a gel. Lotions may be used with any skin type, and are preferred to spread over hairy areas.
Salicylic acid 2% (eg, Stri-Dex, Fostex) has anti-inflammatory and mild comedolytic effects, and has been shown to be more effective than placebo in clinical trials.10 It is generally well tolerated and should be applied only once or twice daily.
Pharmacists may be the point of initial contact for many patients with acne and can effectively dispel the many myths regarding this disorder. Pharmacists should encourage appropriate skin hygiene, recommend benzoyl peroxide for mild cases, counsel patients to remain compliant with therapy, and remind them that improvement may not be seen for 4 to 6 weeks.
For a list of references, send a stamped, self-addressed envelope to: References Department, Attn. D. Ryan, Pharmacy Times, 241 Forsgate Drive, Jamesburg, NJ 08831; or send an e-mail request to: email@example.com.