Common Brand Names: Rocephin
Therapeutic Class: A third-generation cephalosporin antibiotic
Common Injectable Dosage Forms:
Powder for Injection: 250 mg, 500 mg in vials, 1 g, 2 g in vials and piggybacks, 10 g in bulk containers
Injection: 1 g and 2 g in 50 mL frozen premix
The usual dose in children 12 years and older and adults is 1-2 g given once daily or in equally divided doses twice daily. Doses of 4 g daily (maximum) may be needed for CNS infections.
The usual dosage for neonates and children 12 years and younger is 50-75 mg/kg daily in equally divided doses every 12 hours, although 100 mg/kg is recommended in CNS infections.
Dosage reductions are not necessary in renal impairment.
Administration and Stability:
For direct IV injections, vials should be reconstituted with sterile water to a concentration of approximately 100 mg/mL and injected over a period of 2-4 minutes. Intermittent IV infusion may be administered after diluting with 50-100 mL of a compatible IV solution and infused over a period of 15-30 minutes. Solutions for IM injection are prepared by adding sterile water or 1% lidocaine to provide a solution of approximately 250 mg/mL and injecting deeply into a large muscle. Stability in vials is 3 days at room temperature and 10 days refrigerated when diluted to 100 mg/mL. After further dilution, the stability is 26 weeks when frozen. pH 6-8
Pharmacology/Pharmacokinetics:
Ceftriaxone exerts its bactericidal activity by inhibition of mucopeptide synthesis in the bacterial cell wall. Ceftriaxone is active against many gram-negative (including Klebsiella species, P. mirabilis, E. coli, H. influenzae, N. meningitidis, and some strains of Pseudomonas aeruginosa), gram-positive bacteria (S. aureus, streptococci) and anaerobic organisms. It is highly resistant to beta-lactamases. It is 100% bioavailable following IM injection, with peak levels occurring in 1-2 hours. The drug is eliminated by biliary and renal excretion, and dose adjustments are not required in most renal/hepatic dysfunction patients. The elimination half-life is 5-9 hours.
Drug and Lab Interactions:
Studies indicate that concurrent administration of ceftriaxone and aminoglycosides may have additive or synergistic activities against some strains of Enterobacteriaceae and P. aeruginosa. One patient reported a disulfiram-like reaction when alcohol was ingested while of ceftriaxone. Like most cephalosporins, urine glucose determinations with Benedict’s reagent may be false-positive.
Contraindications/Precautions:
Should be used with caution in patients who report a previous history of sensitivity to penicillins. Use caution when giving by the IV route due to the possibility of thrombophlebitis. Pain, tenderness, and tissue sloughing may occur with IV extravasation or upon IM injection. Cephalosporins may cause superinfections. Pregnancy Category B.
Monitoring Parameters:
Watch for signs and symptoms of anaphylaxis.
Adverse Effects:
The most common adverse effects are nausea, diarrhea, and rash. Blood dyscrasias, hypothrombinemia, and hepatic abnormalities have occurred, as well as cutaneous reactions.
Common Clinical Applications:
Used for the treatment of lower respiratory tract infections, skin and skin structure infections, bone and joint infections, intra-abdominal infections, urinary tract infections, meningitis, septicemia, and gonorrhea caused by susceptible organisms. It is also used for perioperative prophylaxis. Its long serum half-life and daily dosing has made it particularly useful in the outpatient management of infections.