What is Rocephin (ceftriaxone)?

What is Rocephin (Ceftriaxone)?

Rocephin is the brand name for ceftriaxone, a third-generation cephalosporin antibiotic administered exclusively by intravenous (IV) or intramuscular (IM) injection for treating serious bacterial infections. 1

Drug Classification and Formulation

• Ceftriaxone is a semisynthetic, broad-spectrum cephalosporin antibiotic that cannot be taken orally because it is not absorbed adequately from the gastrointestinal tract. 1, 2
• The drug is supplied as a sterile powder that must be reconstituted for IV or IM administration. 1
• Each gram of ceftriaxone contains approximately 83 mg (3.6 mEq) of sodium. 1

Antimicrobial Spectrum

Gram-Negative Coverage

• Ceftriaxone demonstrates excellent activity against many gram-negative aerobic bacteria including Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Haemophilus influenzae, and Neisseria gonorrhoeae (including penicillinase-producing strains). 1, 3
• The CDC recommends ceftriaxone for uncomplicated urogenital and anorectal gonococcal infections with 98.9% cure rates. 4
• It has some activity against Pseudomonas aeruginosa, but cannot be recommended as sole therapy for pseudomonal infections. 3

Gram-Positive Coverage

• Ceftriaxone has moderate activity against Streptococcus pneumoniae and good activity against methicillin-susceptible Staphylococcus aureus (MSSA), though cefazolin is preferred for MSSA infections. 4
• It has no activity against methicillin-resistant Staphylococcus aureus (MRSA). 4
• The drug shows limited activity against drug-resistant S. pneumoniae (DRSP). 4

Anaerobic Coverage

• Ceftriaxone has some activity against anaerobes including Bacteroides fragilis and Peptostreptococcus species. 1
• Most strains of Clostridium difficile are resistant. 1

FDA-Approved Indications

Ceftriaxone is indicated for infections caused by susceptible organisms in the following sites: 1

• Lower respiratory tract infections (pneumonia, bronchitis)
• Acute bacterial otitis media (though single-dose therapy may have lower cure rates than 10-day oral therapy)
• Skin and skin structure infections
• Urinary tract infections (complicated and uncomplicated)
• Uncomplicated gonorrhea (cervical, urethral, rectal, and pharyngeal)
• Pelvic inflammatory disease (must add antichlamydial coverage as ceftriaxone has no activity against Chlamydia trachomatis)
• Bacterial septicemia
• Bone and joint infections
• Intra-abdominal infections
• Meningitis (caused by H. influenzae, N. meningitidis, or S. pneumoniae)
• Surgical prophylaxis (single 1 gram preoperative dose for contaminated or potentially contaminated procedures)

Unique Pharmacokinetic Advantage

• Ceftriaxone has an exceptionally long serum half-life of 5.8-8.7 hours (mean 6.5 hours), which is the longest among third-generation cephalosporins. 5
• This extended half-life allows for once-daily dosing in most adults and every 12 hours in children, offering significant convenience and cost advantages over other antibiotics requiring multiple daily doses. 6, 5
• The drug achieves complete absorption following IM administration, with peak plasma concentrations occurring 2-3 hours after injection. 2
• It distributes well throughout all body spaces, including cerebrospinal fluid in the presence of meningeal inflammation. 5

Oral Alternatives

• Ceftriaxone has no oral formulation. 7, 2
• Cefixime 400 mg orally is the standard oral cephalosporin substitute when oral therapy is appropriate (e.g., for gonorrhea). 7, 2
• However, cefixime provides lower and less sustained bactericidal levels than ceftriaxone 125 mg IM, with higher failure rates for pharyngeal gonorrhea (5.8% vs 1.8%). 7

Clinical Efficacy

• Clinical studies have consistently demonstrated bacteriologic and clinical success rates exceeding 90% for serious bacterial infections. 5
• In a study of 125 patients with severe bacteremic infections, single daily dose ceftriaxone achieved complete recovery in 84.8% of patients. 8
• The drug has been effective in treating infections due to multidrug-resistant Enterobacteriaceae. 3

Safety Profile

• Ceftriaxone has been well tolerated, with diarrhea being the most common adverse effect, though it rarely requires discontinuation of therapy. 6
• No unique toxicities have been identified, and hypoprothrombinemic bleeding is not part of the adverse reaction profile. 5
• Adverse reactions characteristic of cephalosporins (e.g., hypersensitivity reactions, gastrointestinal disturbances) have been observed. 5

Important Clinical Considerations

• Dosage modification is necessary only when there is combined hepatic and renal dysfunction. 5
• When used for pelvic inflammatory disease, appropriate antichlamydial coverage must be added since ceftriaxone has no activity against Chlamydia trachomatis. 1
• The drug should not be used as monotherapy for infections treatable with narrower-spectrum agents (e.g., cefazolin for MSSA) to minimize resistance development. 4
• For intra-abdominal infections, combination with metronidazole is recommended for anaerobic coverage. 4