Which first-line treatment is effective for non-severe Clostridium difficile infection?

Metronidazole is indeed the recommended first-line treatment for non-severe Clostridium difficile infection (CDI). This choice is grounded in clinical guidelines, which indicate that metronidazole is effective in treating mild to moderate cases of CDI. It acts by disrupting the DNA synthesis of the bacteria, thereby helping to eliminate the infection.

While vancomycin is also an effective treatment for CDI, it is typically reserved for cases that are severe or in cases where a patient has had multiple recurrences or metronidazole treatment has failed. Rifaximin and doxycycline are not standard treatments for CDI. Rifaximin, while effective for some gastrointestinal conditions, does not have clinical trial support for CDI treatment, and doxycycline is generally not used for CDI as it does not target the specific bacterial strains involved.

This distinction in treatment regimens highlights the importance of carefully assessing the severity of the infection in guiding appropriate therapy choices. In the case of non-severe CDI, metronidazole remains the go-to option based on evidence and clinical guidelines.