Acne formulations, benzoyl peroxide

It is available with or without a prescription and remains the most commonly purchased over-the-counter topical treatment for acne.12 Benzoyl peroxide is available in concentrations ranging from 1% to 10% in various formulations including creams, lotions, gels, and facial washes. 

Retinoids, which are highly effective in the treatment of acne, stimulate epithelial cell turnover and aid in unclogging blocked pores. Retinoids also exhibit anti-inflammatory properties through the inhibition of neutrophil and monocyte chemotaxis.8 Because of these comedolytic and antiinflammatory effects, topical retinoids are recommended as first-line treatment for mild to moderate comedonal and inflammatory acne.3 While success is seen with monotherapy, using a retinoid in combination with benzoyl peroxide or topical antibacterials is also an appropriate and effective therapeutic treatment option.3 Tretinoin, adapalene, and tazarotene are topical retinoids available for use in the treatment of acne. Table 62-2 describes the strengths and formulations of these agents. 

Clindamycin has in vitro activity against Propionibacterium acnes this has been postulated as the mechanism of its beneficial effect in acne therapy. Approximately 10% of an applied dose is absorbed, and rare cases of bloody diarrhea and pseudomembranous colitis have been reported following topical application. The hydroalcoholic vehicle may cause drying and irritation of the skin, with complaints of burning and stinging. The water-based gel and lotion formulations are well tolerated and less likely to cause irritation. Allergic contact dermatitis is uncommon. Clindamycin is also available in a fixed-combination topical gel with benzoyl peroxide (BenzaClin). 

A 17-year-old girl, Miss EV, presents in your pharmacy with her regular prescription for Microgynon 30. Three months ago she had complained of problems of acne so you recommended that she try an over-the-counter topical benzoyl peroxide formulation. Her acne does not appear to have improved from the treatment so you recommend that she makes an appointment to see her GP. The following week she presents a new prescription for oxytetracycline tablets (500 mg b.d.). 

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