A patient with community-acquired pneumonia is treated with ceftriaxone. Which statement accurately describes its pharmacokinetic advantage over cefazolin for outpatient parenteral therapy?

• A Ceftriaxone has a half-life of approximately 8 hours, allowing once-daily dosing ✓
• B Ceftriaxone has a shorter half-life, requiring more frequent administration
• C Ceftriaxone is primarily eliminated by the kidney, unchanged, and has no biliary excretion
• D Ceftriaxone penetrates the CSF only when meninges are non-inflamed

Explanation

Ceftriaxone has an unusually long half-life of approximately 6–9 hours among third-generation cephalosporins, enabling once-daily dosing and making it ideal for outpatient parenteral antibiotic therapy (OPAT). It undergoes dual elimination: about 60% hepatic/biliary and 40% renal, which distinguishes it from most other cephalosporins (predominantly renal). It penetrates inflamed meninges well, making it the drug of choice for bacterial meningitis.

Reference: KD Tripathi, Essentials of Medical Pharmacology, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.