Monocef (Ceftriaxone) Dosing: Once Daily (OD) or Twice Daily (BD)
Monocef (ceftriaxone) should be administered once daily (OD) for most infections, with twice daily (BD) dosing reserved only for specific severe infections such as meningitis and endocarditis.
Standard Dosing Recommendations
- Ceftriaxone is typically administered once daily due to its long half-life, which allows for a convenient once-daily administration schedule 1, 2
- The standard adult daily dose is 1-2 grams given once daily depending on the type and severity of infection 1
- For most infections, the once-daily dosing regimen has been proven to be as effective as more frequent administration 2, 3
- The FDA-approved labeling states: "The usual adult daily dose is 1 to 2 grams given once a day (or in equally divided doses twice a day) depending on the type and severity of infection" 1
Specific Infection Scenarios
- For common infections such as urinary tract infections, lower respiratory tract infections, skin and soft tissue infections, and uncomplicated bacteremia, once-daily dosing is recommended 1, 4
- For skin and soft tissue infections, ceftriaxone 1g once daily has been shown to be effective in clinical trials 4
- For bacterial meningitis in children, ceftriaxone can be administered as a single daily intravenous dose of 100 mg/kg on day one, followed by 80 mg/kg daily 5
Exceptions Requiring Twice Daily (BD) Dosing
- For bacterial meningitis in adults, ceftriaxone should be administered at 2 grams IV every 12 hours (twice daily) 6
- For gonococcal meningitis and endocarditis, ceftriaxone 1-2 grams IV every 12 hours is recommended 6, 7
- For infections caused by bacteria with elevated minimum inhibitory concentrations (MICs), twice-daily dosing may be required 7, 6
Practical Considerations
- The total daily dose should not exceed 4 grams regardless of dosing frequency 1
- For pediatric patients, the recommended total daily dose is 50-75 mg/kg given once daily (or in equally divided doses twice a day) for most infections 1
- For pediatric meningitis, a higher dose of 100 mg/kg/day (not exceeding 4 grams daily) is recommended, which can be administered once daily or divided every 12 hours 1
- No dosage adjustment is necessary for patients with impairment of renal or hepatic function unless severe 1
Conclusion on Dosing Frequency
- Once-daily (OD) administration of ceftriaxone is appropriate for most infections due to its long half-life and has been shown to be as effective as more frequent dosing regimens 2, 3, 8
- Twice-daily (BD) dosing should be reserved for severe infections such as meningitis, endocarditis, or infections caused by organisms with elevated MICs 6, 7