Recommendations for treatment are based on international guidelines [ICSI, 2006; Strauss et al, 2007] and narrative reviews [Webster, 2002; James, 2005; Ravenscroft, 2005; Zaenglein and Thiboutot, 2006; Acne Working Group, 2008], and reflect published data from randomized controlled trials (RCTs) where available, and otherwise, expert opinion.

Referral

• Referral of all people with severe acne vulgaris is consistent with Referral advice: A guide to appropriate referral from general to specialist services, published by the National Institute for Health and Clinical Excellence (NICE) [NICE, 2001]. This is recommended in order to alleviate pain and psychological distress, and to prevent or limit scarring.

Oral antibiotics

• Oral antibiotics are universally recommended by experts for the treatment of severe acne, or extensive acne that would be difficult to treat with a topical drug [Dreno et al, 2004; ICSI, 2006; Strauss et al, 2007].
• Oral tetracyclines are recommended first-line. There is good evidence from placebo-controlled trials that tetracycline is effective at reducing lesion counts and severity. Although there is a lack of placebo-controlled trials to verify the efficacy of the other standard tetracyclines, there is evidence from comparative trials that there is likely to be a class effect.
• Oral erythromycin should be reserved for use when tetracyclines are contraindicated.
• There is a lack of evidence from placebo-controlled trials to verify the efficacy of erythromycin, although evidence from comparative trials indicate it is probably as effective as tetracyclines.
• However, there is evidence from observational and controlled studies that there are particular problems with the development of bacterial resistance to erythromycin.
• Minocycline is increasingly not recommended for the treatment of acne vulgaris as other tetracyclines are regarded as being as effective, and less expensive with a better safety profile [DTB, 2006; DTB, 2009].

Combining oral and topical drugs

• There is little evidence from RCTs to confirm the effectiveness of combining oral and topical treatment, but expert consensus supports this practice [Dreno et al, 2004].
• Combining an oral antibiotic with a topical retinoid targets both inflammatory and non-inflammatory lesions, and inhibits the formation of microcomedones (the precursors of acne).
• For long-term use (such as over 3 months), addition of benzoyl peroxide should be considered, to prevent the development of bacterial resistance [Ozolins et al, 2005].
• Oral and topical antibiotics should never be combined (as this increases the risk of antibiotic resistance without giving additional benefit) [Dreno et al, 2004].

Combined oral contraceptives (COCs)

• COCs are recommended as a first-line adjunctive treatment for women who have acne [ICSI, 2006; Strauss et al, 2007]. There is good evidence from placebo-controlled trials that COCs are effective in reducing lesion count, acne severity, and the woman's perception of the condition [Arowojolu et al, 2007].
• Co-cyprindiol is licensed for 'severe acne, refractory to prolonged oral antibiotic therapy; or moderately severe hirsutism' [ABPI Medicines Compendium, 2008a]. However, some experts suggest it may be appropriate to use it in suitable women before antibiotics are tried, and this is commonly done in practice.