Combination of Low- Dose Isotretinoin and Pulsed Oral Azithromycin in the Management of Moderate to Severe Acne

Background: The conventionally used dose of isotretinoin in acne causes significant dose-related adverse effects. Low-dose isotretinoin has been used successfully in mild to moderate papulopustular acne. Although isotretinoin acts against all mechanisms of acne formation, it has no significant direct antimicrobial effect.

Objective: To test whether the addition of an antibacterial enables use of isotretinoin in low doses even in moderate to severe acne. Methods: This was a preliminary open-label, prospective, non-comparative, single-centre study carried out in a tertiary-care referral hospital. Seventy patients with grade 3 and 4 acne according to the US FDA global score were included in the study between October 2005 and December 2007. These patients were treated with a combination of low-dose isotretinoin (0.3 mg/kg/day) and pulsed oral azithromycin (500 mg/day over three consecutive days every 2 weeks). Response to treatment was assessed at monthly intervals and was recorded as a percentage decrease in overall severity of disease. Treatment was continued to complete clearance of lesions or to 16 weeks, whichever came later.

Results: Sixty-two (93.9%) of 66 eligible patients had complete clearance of disease activity after a mean treatment duration of 21 weeks. The mean total cumulative dose of isotretinoin was 49.6 mg/kg. Seven (11.3%) patients had a relapse of disease during the post-treatment follow-up period. Fifty-three adverse effects were observed. Three patients had initial aggravation of disease that was managed with prednisolone and disappeared with continuation of treatment.

Conclusion: A combination of low-dose isotretinoin and oral azithromycin pulse is effective in severe acne and has a reasonably acceptable adverse-effect profile and low post-treatment relapse rates.