Ceftriaxone

Ceftriaxone is a broad-spectrum third-generation cephalosporin antibiotic used to treat a variety of bacterial infections. It is administered by intravenous or intramuscular injection and is noted for a relatively long half-life, which often allows once-daily dosing. It is commonly employed for meningitis, community-acquired pneumonia, intra-abdominal and gynecologic infections, complicated urinary tract infections, and gonorrhea, among others.

Ceftriaxone exerts its effect by binding to penicillin-binding proteins and inhibiting bacterial cell wall synthesis, leading to bactericidal activity. Its spectrum includes many Gram-positive cocci such as Streptococcus pneumoniae and certain Gram-negative aerobes including Neisseria species, Haemophilus influenzae, and Enterobacterales. It is less active against enterococci and does not reliably cover Pseudomonas aeruginosa or many anaerobes; activity against MRSA is limited.

Pharmacokinetics and administration considerations: ceftriaxone is eliminated primarily by biliary excretion and has a half-life of about 6–9 hours in adults, supporting once-daily dosing for many infections. Renal impairment often does not require dose adjustment, but hepatic disease and biliary complications can affect levels. It is not recommended for use in neonates younger than 28 days due to the risk of bilirubin displacement and kernicterus. In addition, it should not be mixed with calcium-containing IV solutions, especially in neonates, and should not be administered in the same IV line as calcium-containing products.

Adverse effects and cautions: common effects include diarrhea, rash, and hypersensitivity reactions. Rare but serious risks include Clostridioides difficile infection and biliary sludge or cholelithiasis. Cross-sensitivity with penicillins can occur. Interactions include potential increased levels with probenecid and coagulation disturbances in patients on anticoagulants.