
Androgens lead to increased sebum production 2 3
- Sebum is produced by the pilosebaceous glands, which are predominantly found on the face, back and chest
- This may be due to an increased response to normal levels of androgens
- Abnormal proliferation and differentiation of keratinocytes leads to comedone formation
Colonisation with Propionibacterium acnes (P. acnes) 2 3
- Sebum and comedone formation alters the micro environment in the pilosebaceous duct, which leads to colonisation of the duct
- Acne lesions begin with an initial inflammatory event, triggered by an infiltration of inflammatory cells
Stages of acne 4

Stages of acne. (A) Normal follicle; (B) open comedone (blackhead); (C) closed comedone (whitehead); (D) papule; (E) pustule.
Common causes of acne 2
- Increased androgens/sebum production in puberty
- Hormones
- Resistance bacteria
- Use of cosmetics
- Drugs
- Smoking
- Stress (increased androgen production)
- Genetics
References:
- Bhate K et al. Br J Dermatol 2013;168(3):474–485.
- Yentzer BA et al. Cutis 2010;86:94–99.
- Ayer J et al. Postgrad Med J 2006;82:500–506.
- Williams C et al. Am J Clin Dermatol 2006;7(5):281–290.
- Dunn LK et al. Derm Online J 2011;17(1):1.
- Krakowski AC et al. Pediatr Dermatol 2008;25(Suppl 1):1–14.
- Primary Care Dermatology Society. Acne Vulgaris. Available at: www.pcds.org.uk/clinical-guidance/acne-vulgaris. (Accessed March 2017).
- Dawson AL, Dellavalle RP et al. Br Med J 2013;346:f2634.
- Goodman G. Am J Clin Dermatol 2009;10(Suppl. 1):1–6.
- Layton AM. Am J Clin Dermatol 2001;2(3):135–141.
Adverse events should be reported directly to the HPRA; Freepost, Pharmacovigilance Section, Health Products Regulatory Authority, Earlsfort Terrace, Dublin 2, Tel: +353 1 676 4971 medsafety@hpra.ie. Adverse events should also be reported to GlaxoSmithKline on 1800 244 255.
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