Antibiotic creams make cutaneous infections more likely

Antibiotics and antiseptics disrupt skin microbiota, which increases the risk of colonization by pathogenic bacteria.

Although soap is useful for removing bacteria picked up from the environment, it isn’t good to remove all bacteria from the skin. A study conducted at the University of Pennsylvania shows that antibiotic creams (used in the treatment of acne, for example) and, to a lesser extent, antiseptics (alcohol, Betadine, etc.) disrupt the composition of the cutaneous microbiota, to the point of increasing the risk of skin infection by pathogenic bacteria.

Researchers applied and reapplied various antibiotics and antiseptics to the skin of mice. They observed changes in the composition of the microbiota (more significant following the application of antibiotics than antiseptics), which persisted for several days after treatment, to the point of increasing the risk of Staphylococcus aureus infection (a pathogenic bacteria and the leading cause of hospital-acquired infections). This phenomenon is due to the reduction in the populations of other, non-pathogenic staphylococci, whose presence on the skin acts as a barrier to the colonization of Staphylococcus aureus. This is further proof that antibiotics—even for the skin—should not be prescribed automatically.

Sources
SanMiguel AJ et al. Topical antimicrobial treatments can elicit shifts to resident skin bacterial communities and reduce colonization by Staphylococcus aureus competitors. Antimicrob Agents Chemother. 2017 Jun 19. http://aac.asm.org/content/early/2017/06/13/AAC.00774-17.long