Thirty patients commencing
isotretinoin for
acne were entered into a double-blind, randomized, placebo-controlled trial to investigate the effect of pulsed intra-nasal
mupirocin ointment on Staphylococcus aureus colonization and
isotretinoin-related side-effects. In both
mupirocin and placebo groups there was an increase in isolation of S. aureus throughout the period of treatment with
isotretinoin from the anterior nares, facial skin and lips. However, these increases were significantly less in the
mupirocin-treated group. A high proportion of all patients suffered inflammatory side-effects of
isotretinoin such as
cheilitis and nasal vestibulitis, with their maximum severities being recorded 2 months after starting
isotretinoin. In spite of the smaller increase in S. aureus colonization in the
mupirocin-treated group no difference was demonstrated in either the incidence of specific S. aureus
infections (e.g.
furunculosis) or the prevalence of
isotretinoin-related inflammatory side-effects. Furthermore, no relationship between the presence of S. aureus and the severity of inflammatory side-effects was shown. Streptococcus species were isolated on four separate occasions from four different patients during the study but their pathogenicity was unclear. These findings suggest that although pulsed intra-nasal
mupirocin produces a significant reduction in
isotretinoin-related staphylococcal colonization, its routine use cannot be justified on the basis of clinical benefit.