What is the recommended dose and treatment duration of ceftriaxone (Ceftriaxone) for bacterial meningitis?

Ceftriaxone for Bacterial Meningitis: Dosing and Duration

For bacterial meningitis in adults, administer ceftriaxone 2 grams IV every 12 hours (total 4 grams daily), with treatment duration of 5 days for meningococcal meningitis, 10-14 days for pneumococcal meningitis, and 21 days for Listeria. 1, 2

Dosing Recommendations by Pathogen

Meningococcal Meningitis (N. meningitidis)

• Dose: 2 grams IV every 12 hours 1, 2
• Duration: 5 days if patient has recovered by day 5 1, 3
• Critical consideration: If ceftriaxone is NOT used, add a single dose of ciprofloxacin 500 mg orally to eradicate throat carriage 1, 4

Pneumococcal Meningitis (S. pneumoniae)

• Dose: 2 grams IV every 12 hours 1, 2
• Duration: 10 days if stable and recovered by day 10; extend to 14 days if taking longer to respond 1, 3
• Penicillin-sensitive strains (MIC ≤0.06 mg/L): May use benzylpenicillin 2.4 grams IV every 4 hours as alternative 1
• Penicillin/cephalosporin-resistant strains: Continue ceftriaxone 2 grams IV every 12 hours PLUS vancomycin 15-20 mg/kg IV every 12 hours PLUS rifampicin 600 mg IV/oral every 12 hours for 14 days 1, 2

Haemophilus influenzae Meningitis

• Dose: 2 grams IV every 12 hours 1, 2
• Duration: 10 days 1, 3

Enterobacteriaceae (Gram-negative bacilli)

• Dose: 2 grams IV every 12 hours 1, 2
• Duration: 21 days 1, 3

Pediatric Dosing

Children and Infants (>28 days old)

• Initial dose: 100 mg/kg IV (maximum 4 grams) 5
• Maintenance: 100 mg/kg/day IV (maximum 4 grams daily), administered once daily OR divided every 12 hours 5, 6
• Duration: 7-14 days depending on pathogen 5
• Evidence: Studies demonstrate CSF concentrations 10-100 fold higher than MIC even 24 hours after dosing 7, 8

Neonates (≤28 days)

• Dose: 25-50 mg/kg/day IV in a single daily dose 2
• Duration: 7 days (10-14 days if meningitis documented) 2
• Critical warning: Infuse over 60 minutes to reduce risk of bilirubin encephalopathy 5
• Contraindication: Do NOT use in hyperbilirubinemic or premature neonates, or those requiring calcium-containing IV solutions 5

Age-Based Empirical Treatment Algorithm

Adults <60 years

• Ceftriaxone 2 grams IV every 12 hours 1, 2
• Add vancomycin 15-20 mg/kg IV every 12 hours OR rifampicin 600 mg every 12 hours if penicillin-resistant pneumococci suspected (e.g., recent travel from high-resistance areas) 1, 2

Adults ≥60 years

• Ceftriaxone 2 grams IV every 12 hours PLUS amoxicillin 2 grams IV every 4 hours to cover Listeria monocytogenes 1, 2
• Add vancomycin or rifampicin if penicillin resistance suspected 1

Critical Administration Details

Infusion Parameters

• Adults: Infuse over 30 minutes 5
• Neonates: Infuse over 60 minutes to reduce bilirubin encephalopathy risk 5
• Concentration: 10-40 mg/mL recommended 5

Calcium Interaction Warning

• Never mix with calcium-containing solutions (Ringer's, Hartmann's, parenteral nutrition) due to precipitation risk 5
• In non-neonates, may administer sequentially if lines thoroughly flushed between infusions 5
• Absolutely contraindicated in neonates receiving calcium-containing IV solutions 5

Evidence Supporting Twice-Daily vs Once-Daily Dosing

The guidelines uniformly recommend twice-daily dosing (every 12 hours) for meningitis to ensure adequate CSF concentrations throughout the dosing interval. 1, 2 While research studies have demonstrated efficacy with once-daily dosing 7, 9, 8, showing CSF trough levels 10-100 fold above MIC even 24 hours post-dose 7, 8, and mean CSF concentrations of 3.5 mcg/mL at trough 9, current authoritative guidelines prioritize twice-daily administration for this life-threatening infection 1, 2.

Common Pitfalls to Avoid

• Do not shorten pneumococcal meningitis treatment to 5-7 days based on early improvement—minimum 10 days required, extending to 14 days if delayed response 1, 3
• Do not forget Listeria coverage in patients ≥60 years—add amoxicillin empirically 1, 2
• Do not use once-daily dosing for meningitis despite pharmacokinetic data supporting it—guidelines recommend twice-daily for CNS infections 1, 2
• Do not administer ceftriaxone to hyperbilirubinemic neonates or mix with calcium-containing solutions 5
• Do not forget carriage eradication if using benzylpenicillin instead of ceftriaxone for meningococcal disease 1, 4

Treatment Duration Summary

Pathogen	Duration	Extension Criteria
N. meningitidis	5 days	Extend if not recovered [1,3]
S. pneumoniae	10 days	14 days if delayed response [1,3]
S. pneumoniae (resistant)	14 days	Fixed duration [1,3]
H. influenzae	10 days	Extend if not responding [1,3]
Enterobacteriaceae	21 days	Extend if not responding [1,3]
Listeria monocytogenes	21 days	Due to intracellular nature [3]