Table 1:

Managing Clostridium difficile infection according to severity¹

Type of infection	Severity	Treatment	Duration of treatment	Author comments
Initial episode or first recurrence	Mild to moderate*	Metronidazole (500 mg orally, 3 times/d)	10–14 d	Avoid metronidazole after first recurrence because of potential cumulative neurotoxicity; consider vancomycin when metronidazole is ineffective, poorly tolerated or contraindicated; fidaxomicin may be equally effective;3 time to resolution may be shorter with vancomycin
	Severe†	Vancomycin (125 mg orally, 4 times/d) with or without metronidazole (500 mg intravenously, 3 times/d)
Complicated‡	Ileus, toxic megacolon, signs of shock	Vancomycin (500 mg orally or rectally, 4 times/d) with metronidazole (500 mg intravenously, 3 times/d)	10–14 d	Consider colectomy for progressive infection in patients with severe illness
Second or later recurrence‡	Mild to moderate*	Vancomycin, tapering§ or pulsed regimen	Example tapering regimen:3 125 mg 4 times/d for 14 d 125 mg 2 times/d for 1 wk 125 mg 1 time/d for 1 wk 125 mg every 2 d for 1 wk 125 mg every 3 d for 2 wk	Consider Saccharomyces boulardii (500 mg, 2 times/d) as adjunctive therapy3
	Severe†	Vancomycin (500 mg orally or rectally, 4 times/d) with metronidazole (500 mg intravenously, 3 times/d)	When acute phase has resolved, consider tapering regimen as above	Avoid S. boulardii in patients who are critically ill

^*Peak leukocytosis < 15 × 10⁹ cells/L, peak serum creatinine < 1.5 times premorbid level.

^†Peak leukocytosis > 15 × 10⁹ cells/L and peak serum creatinine level ≥ 1.5 times premorbid level.

^‡Expert consultation recommended (author opinion).

^§Regimen may vary across institutions.³