What is the medication and dosage that is first-line for treating C. difficile infection?

Vancomycin is indeed the first-line treatment for Clostridium difficile infection, particularly in cases of moderate to severe infection. The recommended dosage of 125 mg taken by mouth four times a day for a duration of 10 to 14 days is supported by clinical guidelines, which have shown this regimen to be effective in eradicating the infection and reducing the risk of recurrence.

This dosing schedule ensures adequate drug exposure to effectively target the bacteria while minimizing the potential for resistance. The oral route is crucial since C. difficile infections primarily involve the colon, and vancomycin's local effect within the gut is necessary for successful treatment.

Other treatment options, while they may have their own indications or scenarios where they are utilized, are not considered first-line for managing C. difficile infections in the same way vancomycin is at this specific dosage and duration.