Vancomycin is recommended as a first-line therapy for severe Clostridium difficile infection (CDI). Due to the high cost of commercially available vancomycin capsules, hospitals frequently compound oral solution despite a lack of data comparing outcomes. This study was conducted to determine treatment outcome differences based on oral vancomycin formulation.

Medical charts of 76 patients with an initial episode of severe CDI receiving oral vancomycin as a commercially available capsule or a compounded oral solution for at least 72 hours were retrospectively reviewed. The primary objective was to compare the time to clinical cure of CDI.

Baseline characteristics between groups were similar except for the median lactate, which was higher in compounded oral solution group (1.5 vs 0.6 mmol/L, P < .001). There was no difference in clinical cure at day 10 (64% solution vs 59% capsules, P = .664). Median time to clinical cure was 8 days for solution and 7 for capsules (P = .597). After adjustment, the hazard ratio of time to clinical cure for solution compared to capsules was 1.15 (P = .69). No significant differences in mortality, recurrence, or complications were noted.

Formulation of oral vancomycin did not impact treatment outcomes in this retrospective study.