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Acne Vulgaris — SCE Dermatology MCQ

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EasyInflammatory DermatosesAcne VulgarisSCE Dermatology

A 25-year-old man with moderate acne is prescribed combined topical retinoid (Adapalene) and topical benzoyl peroxide. His dermatologist explains why benzoyl peroxide should always be combined with topical or oral antibiotics when used for acne. What is the reason?

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Correct answer: E — BPO reduces the development of antibiotic-resistant Propionibacterium acnes (Cutibacterium acnes)

Benzoyl peroxide (BPO) is a potent antimicrobial with a unique mechanism (oxidative release of free radicals) that does not induce bacterial resistance. BAD guidelines mandate that BPO should be combined with any topical or oral antibiotic used for acne to prevent the emergence of antibiotic-resistant C. acnes. The combination of BPO with a topical retinoid (e.g., Adapalene/BPO fixed combination — Epiduo) addresses multiple acne pathogenic factors: retinoid normalises follicular keratinisation, BPO kills bacteria without resistance, and the combination is more effective than either alone. Topical antibiotics should NEVER be used as monotherapy for acne (resistance concerns).

Reference: BAD 2023 Acne Guidelines; NICE CKS