What is the dose of oral vancomycin?

Oral Vancomycin Dosing

For C. difficile-associated diarrhea, the recommended oral vancomycin dose is 125 mg administered 4 times daily for 10 days. 1

Adult Dosing Guidelines

Oral vancomycin is specifically indicated for two conditions:

1. C. difficile-associated diarrhea

   • 125 mg administered orally 4 times daily for 10 days 1

2. Staphylococcal enterocolitis

   • 500 mg to 2 g total daily dose administered orally in 3 or 4 divided doses for 7 to 10 days 1

Pediatric Dosing Guidelines

For patients less than 18 years of age:

• Both C. difficile-associated diarrhea and staphylococcal enterocolitis:
  • 40 mg/kg/day in 3 or 4 divided doses for 7 to 10 days 1
  • Total daily dosage should not exceed 2 g 1

Important Clinical Considerations

Route of Administration

• Oral vancomycin is not systemically absorbed when used for treatment of C. difficile or staphylococcal enterocolitis 1
• Parenteral (IV) vancomycin is not effective for C. difficile-associated diarrhea or staphylococcal enterocolitis 1
• Do not confuse oral dosing with IV dosing regimens, which follow completely different protocols 2

Special Populations

• Patients with inflammatory bowel disorders: May have significant systemic absorption of oral vancomycin 1
• Patients with renal insufficiency: May require monitoring of serum concentrations if there is concern for systemic absorption 1
• Elderly patients (>65 years): Higher risk of nephrotoxicity; renal function should be monitored during and following treatment even with oral therapy 1

Potential Adverse Effects

• Nephrotoxicity can occur following oral vancomycin therapy, particularly in patients >65 years 1
• Risk increases with concomitant aminoglycoside therapy 1

Clinical Pearls

• Oral vancomycin is available as 125 mg and 250 mg capsules 1
• Oral vancomycin is contraindicated in patients with known hypersensitivity to vancomycin 1
• For IV vancomycin (different indication), standard dosing for adults with normal renal function is 15-20 mg/kg/dose every 8-12 hours 2
• Do not use oral vancomycin for systemic infections as it is not absorbed from the gastrointestinal tract 1

Common Pitfalls

• Confusing oral and IV dosing regimens
• Failing to recognize potential for systemic absorption in patients with inflamed intestinal mucosa
• Not monitoring renal function in elderly patients receiving oral vancomycin
• Using oral vancomycin for infections other than C. difficile-associated diarrhea or staphylococcal enterocolitis