Ceftriaxone Dosing Frequency
Ceftriaxone is administered once daily for most infections in adults and children, with twice-daily dosing (every 12 hours) reserved specifically for bacterial meningitis and other central nervous system infections. 1, 2
Standard Dosing Frequency by Population
Adults
- Once daily (every 24 hours) is the standard frequency for most infections, including pneumonia, skin/soft tissue infections, urinary tract infections, and uncomplicated bacteremia 1, 2
- The usual adult dose is 1-2 grams given once daily, with a maximum of 4 grams per day 1, 2
- Twice daily (every 12 hours) is required for bacterial meningitis at 2 grams per dose (total 4 grams daily) 3
- Gonococcal meningitis and endocarditis also require twice-daily dosing at 1-2 grams every 12 hours 3
Pediatric Patients (Non-Meningitis)
- Once daily dosing is appropriate for most pediatric infections at 50-75 mg/kg/day 1, 2
- For serious infections other than meningitis, the dose can be divided every 12 hours (50-75 mg/kg/day), not to exceed 2 grams daily 1, 2
- Acute otitis media requires only a single intramuscular dose of 50 mg/kg (maximum 1 gram) 1, 2
Pediatric Meningitis
- Initial dose: 100 mg/kg (maximum 4 grams) 1, 2
- Maintenance: 100 mg/kg/day (maximum 4 grams daily) given once daily OR divided every 12 hours 1, 2
- Duration: 7-14 days typically 1, 2
Neonates and Young Infants
- 8-21 days old: Ampicillin plus ceftazidime or gentamicin (ceftriaxone NOT recommended due to bilirubin displacement risk) 4
- 22-28 days old: Ceftriaxone 50 mg/kg once daily (every 24 hours) for UTI or bacteremia 4
- 29-60 days old: Ceftriaxone 50 mg/kg once daily (every 24 hours) 4
- Neonatal meningitis (22-28 days): Use ampicillin plus ceftazidime every 8 hours instead of ceftriaxone 4
- Infusion time: 60 minutes in neonates (versus 30 minutes in older patients) to reduce bilirubin encephalopathy risk 1, 2
Critical Frequency Considerations by Infection Type
When Twice-Daily Dosing is Mandatory
- Bacterial meningitis (all causes): 2 grams IV every 12 hours in adults 3
- Pneumococcal meningitis: 2 grams IV every 12 hours for 10-14 days 3
- Meningococcal meningitis: 2 grams IV every 12 hours for 5 days 3
- Enterobacteriaceae CNS infections: 2 grams IV every 12 hours for 21 days 3
- Gonococcal meningitis: 1-2 grams IV every 12 hours for 10-14 days 3
The rationale for twice-daily dosing in meningitis is to maintain adequate cerebrospinal fluid concentrations throughout the treatment period, as CNS penetration requires sustained plasma levels 3.
When Once-Daily Dosing is Appropriate
- Disseminated gonococcal infection: 1 gram IM/IV every 24 hours 3
- Uncomplicated gonococcal infections: Single 250 mg IM dose 1, 2
- Skin and soft tissue infections: 1-2 grams IV/IM every 24 hours 1, 2
- Urinary tract infections: 1-2 grams IV/IM every 24 hours (or single dose for uncomplicated cases) 3
- Pneumonia: 1-2 grams IV/IM every 24 hours 1, 2
- Endocarditis (viridans streptococci): 2 grams IV/IM once daily for 4 weeks 3
Common Pitfalls and Caveats
Avoid These Errors
- Do not use once-daily dosing for meningitis - this is inadequate for CNS infections and may lead to treatment failure 3
- Do not use ceftriaxone in hyperbilirubinemic neonates - it displaces bilirubin from albumin, risking kernicterus 1, 2
- Do not mix with calcium-containing solutions - fatal precipitates can form, especially in neonates 1, 2
- Do not underdose pharyngeal gonorrhea - treatment failures reported with 250-500 mg doses when MICs are elevated; consider higher doses 3
Special Populations Requiring Adjustment
- Elderly patients: No frequency adjustment needed up to 2 grams daily unless severe renal/hepatic impairment present 1, 2
- Renal/hepatic impairment: No dosage or frequency adjustment required for isolated renal or hepatic dysfunction 1, 2
- Outpatient parenteral therapy: Once-daily dosing offers significant convenience and cost advantages for home infusion 3