Treatment for the first episode of Clostridioides difficile infection

An overview of managing Clostridioides difficile infection is provided for adults and children younger than 18 years.

Seek expert advice for severe, complicated or fulminant disease (for definitions, see Severity assessment of C. difficile infection). For treatment recommendations, see Severe, complicated or fulminant Clostridioides difficile infection.

In addition to starting antibiotics for C. difficile infection, management includes:

  • starting rehydration strategies (see advice on rehydration for adults or children)
  • stopping any implicated antibiotics unless there is a strong rationale for continuing them. In up to 25% of patients in whom antibiotics are stopped, symptoms resolve and the risk of relapse is reduced. If antibiotics cannot be stopped, seek expert advice
  • avoiding proton pump inhibitors (PPIs) and antimotility drugs
  • considering other factors (eg diet, caffeine, lactose) or medications (eg lactulose) that may exacerbate diarrhoea, or concomitant conditions that can cause similar symptoms (eg inflammatory bowel disease) and modify if possible.

For a first episode of mild to moderate C. difficile infection, evidence in adults suggests that vancomycin has greater efficacy than metronidazole. This is more likely to be explained by differences in pharmacokinetics of the two drugs than resistance of C. difficile to metronidazoleJohnson, 2014Zar, 2007. Metronidazole can be used if vancomycin is not accessible (eg cost is prohibitive).

In children, the relative efficacy of vancomycin and metronidazole is likely to be similar to that in adults. However, the available liquid formulations for use may affect drug choice. Injectable vancomycin is given orally or enterally, often with flavouring syrups. Alternatively, an oral vancomycin suspension is available through the Special Access Scheme. In contrast, metronidazole has a readily available oral liquid formulation that improves palatability and ease of use.

Note: Do not give vancomycin intravenously to treat C. difficile infection.

For the first episode of mild to moderate C. difficile infection in adults and children younger than 18 years, use:

1vancomycin 125 mg (child: 10 mg/kg up to 125 mg) orally or enterally, 6-hourly for 10 days123 vancomycin vancomycin vancomycin

OR

2metronidazole 400 mg (child: 10 mg/kg up to 400 mg) orally or enterally, 8-hourly for 10 days. metronidazole metronidazole metronidazole

Diarrhoea may take several days to respond to appropriate treatment. Data suggest that the median time to resolution of diarrhoea is 2 to 3 days, with most patients responding by 5 daysLouie, 2006.

For patients who have clinically improved, complete the course. For information about follow-up testing and patient education, see Follow-up for patients with Clostridioides difficile infection.

For patients who have not clinically improved after 5 days of therapy, see Treatment of refractory Clostridioides difficile infection.

1 Injectable vancomycin can be given orally or enterally, as an alternative to oral capsules. Dissolve 500 mg of vancomycin powder in 10 mL of water, measure the appropriate dose (eg 125 mg = 2.5 mL), and give orally or enterally. Flavouring syrups can be added before administration to improve palatability. Alternatively, an oral vancomycin suspension is available through the Special Access Scheme.Return
2 Intravenous vancomycin is not effective against C. difficile infection because of inadequate penetration of the drug into the lumen of the colon.Return
3 Systemic absorption of vancomycin can occur with oral or enteral administration. If toxicity is suspected, consider measuring vancomycin plasma concentrations; otherwise, therapeutic drug monitoring is not required.Return