Abstract
The emergence of hypervirulent Clostridioides difficile strains has decreased the efficacy of metronidazole in the treatment of C. difficile infection (CDI). Therefore, revised guidelines no longer recommend the use of metronidazole as a first-line regimen for CDI and restrict its use for non-severe CDI, only when vancomycin and fidaxomicin are unavailable. In Korea, an epidemic caused by a hypervirulent C. difficile strain or the emergence of metronidazole resistant C. difficile strains have not been reported. This review article aims to compare the treatment outcomes and adverse effects of vancomycin and metronidazole and discuss the validity of the guidelines of various agencies, which restrict the use of metronidazole, for Korean patients. There are no substantial adverse effects of metronidazole, and its clinical outcomes against non-severe CDI are similar to those of vancomycin. Based on these findings, we recommend that the use of metronidazole for the treatment of non-severe CDI is still an appropriate option in Korea.