What is the recommended dosage of ceftriaxone for treating bacterial infections?

Ceftriaxone Dosage Guidelines

The recommended dosage of ceftriaxone for treating bacterial infections varies by indication, with adults typically receiving 1 to 2 grams once daily (or in equally divided doses twice daily) depending on infection severity, with a maximum daily dose of 4 grams. 1, 2

Adult Dosing

Standard Adult Dosing

• Usual adult dose: 1-2 grams once daily or divided twice daily 1, 2
• Maximum daily dose: 4 grams 1, 2
• Duration: Generally 4-14 days; longer for complicated infections 1, 2
  • Continue for at least 2 days after signs and symptoms of infection have disappeared
  • For Streptococcus pyogenes infections: minimum 10 days 1, 2

Specific Adult Indications

• Uncomplicated gonorrhea: 250 mg IM as a single dose 3, 1
• Surgical prophylaxis: 1 gram IV 30-120 minutes before surgery 1, 2
• Meningococcal infections: 2 g IV every 12 hours or 2 g cefotaxime IV every 6 hours 4
• Pneumococcal meningitis: 2 g IV every 12 hours for 10-14 days 4
• Bacterial meningitis: 100 mg/kg (maximum 4 grams) initially, then 100 mg/kg/day once daily or divided every 12 hours 3
• Community-acquired pneumonia: 1 g daily has shown similar efficacy to 2 g daily regimens 5

Pediatric Dosing

Standard Pediatric Dosing

• Skin/soft tissue infections: 50-75 mg/kg/day once daily or divided twice daily (maximum: 2 grams/day) 1, 2
• Serious infections (non-meningitis): 50-75 mg/kg/day divided every 12 hours (maximum: 2 grams/day) 1, 2
• Meningitis:
  • Initial dose: 100 mg/kg (maximum: 4 grams)
  • Maintenance: 100 mg/kg/day once daily or divided every 12 hours (maximum: 4 grams/day)
  • Duration: 7-14 days 1, 2
• Acute otitis media: 50 mg/kg IM as a single dose (maximum: 1 gram) 1, 2

Administration Routes

Intravenous Administration

• Administer over 30 minutes (adults) 1, 2
• For neonates: administer over 60 minutes to reduce risk of bilirubin encephalopathy 1, 2
• Recommended concentration: 10-40 mg/mL 1, 2

Intramuscular Administration

• Inject well within a large muscle body 1, 2
• Aspirate to avoid inadvertent intravascular injection 1, 2

Special Populations

Renal/Hepatic Impairment

• No dosage adjustment necessary for patients with impaired renal or hepatic function 1, 2

Elderly Patients

• No modification required for elderly patients up to 2 grams/day, provided there is no severe renal or hepatic impairment 1, 2

Neonates

• Contraindicated in premature neonates 1, 2
• Contraindicated in neonates (≤28 days) requiring calcium-containing IV solutions 1, 2
• Administer IV doses over 60 minutes to reduce risk of bilirubin encephalopathy 1, 2

Important Precautions

Compatibility Issues

• Do not use diluents containing calcium (e.g., Ringer's solution, Hartmann's solution) 1, 2
• Do not administer simultaneously with calcium-containing IV solutions 1, 2
• Compatible with metronidazole hydrochloride at specific concentrations 1, 2

Clinical Pearls

• Once-daily dosing is effective for most infections due to ceftriaxone's long half-life (5-8 hours) 6, 7
• For community-acquired pneumonia, 1 g daily has shown similar efficacy to higher doses 5
• For bacterial meningitis in children, once-daily administration has shown high efficacy (96% CSF sterilization) 7
• When treating Streptococcus pneumoniae infections with uncertain susceptibility, higher doses may be warranted 4

Ceftriaxone's long half-life allows for convenient once-daily dosing in most infections, making it an excellent choice for both inpatient and outpatient parenteral therapy when appropriate.