Ceftriaxone injection

Generic name: ceftriaxone (injection)

Brand names: Rocephin, Aventriax, and Getofin

Drug class: Third generation cephalosporins

Table of Contents

What is ceftriaxone?

Ceftriaxone is a third-generation cephalosporin antibiotic that was first introduced into clinical practice in the 1980s. It represents a significant advancement in antibiotic therapy due to its broad-spectrum activity against a wide range of bacteria, including both gram-positive and gram-negative organisms.Ceftriaxone was developed by Hoffmann-La Roche, now known as Roche, a pharmaceutical company based in Switzerland.

It was discovered through the modification of the cephalosporin nucleus to improve pharmacokinetic properties and broaden the spectrum of activity.

Ceftriaxone belongs to the cephalosporin class of antibiotics, which are beta-lactam antibiotics.

Mechanism of Action

Ceftriaxone works by inhibiting bacterial cell wall synthesis. It does this by binding to and inhibiting the activity of penicillin-binding proteins (PBPs), which are enzymes involved in the final steps of bacterial cell wall synthesis. This leads to the disruption of bacterial cell wall formation, ultimately causing cell lysis and death.

Pharmacokinetics

Route of Administration: Ceftriaxone is typically administered intravenously (IV) or intramuscularly (IM).

Absorption: Ceftriaxone is well-absorbed after intramuscular administration and achieves high concentrations in various body tissues and fluids.

Distribution: It has a wide distribution throughout the body, including penetration into cerebrospinal fluid (CSF), making it effective in treating meningitis.

Metabolism: Ceftriaxone undergoes minimal metabolism in the liver, with the majority of the drug excreted unchanged in the bile. It does not require dose adjustment in patients with hepatic impairment.

Elimination: Ceftriaxone is primarily eliminated unchanged via the kidneys.

Renal Impairment: In patients with renal impairment, the elimination half-life of ceftriaxone may be prolonged, necessitating dose adjustment based on creatinine clearance.

Half-Life: The half-life of ceftriaxone in adults is approximately 5–9 hours, allowing for once-daily dosing in most cases.

Therapeutic Uses

Ceftriaxone is commonly used to treat a wide range of infections caused by susceptible bacteria, including:
- Lower respiratory tract infections (e.g., pneumonia)
- Urinary tract infections (UTIs)
- Skin and soft tissue infections
- Intra-abdominal infections
- Bone and joint infections
- Meningitis
- Gonorrhea
- Lyme disease (particularly in neuroborreliosis)
It is also used prophylactically in certain surgical procedures to prevent postoperative infections.

It’s important to note that ceftriaxone should be used judiciously and only when indicated, as indiscriminate use can contribute to the development of antibiotic resistance. Additionally, it is essential to consider factors such as local susceptibility patterns and individual patient characteristics when prescribing ceftriaxone.

Side effects of ceftriaxone-injection

Ceftriaxone, like any medication, can potentially cause side effects and interact with other drugs. Here’s a rundown of its common side effects and drug interactions:

Gastrointestinal Disturbances: This can include diarrhea, nausea, vomiting, and abdominal pain. Pseudomembranous colitis, a severe form of antibiotic-associated diarrhea caused by a Clostridium difficile infection, can also occur.
Hypersensitivity Reactions: Allergic reactions to ceftriaxone can range from mild rashes to severe anaphylaxis. Patients with a history of penicillin allergy may have an increased risk of allergic reactions to cephalosporins like ceftriaxone.
Biliary Sludging and Gallbladder Pseudolithiasis: Ceftriaxone can cause the formation of precipitates in the gallbladder, leading to biliary sludging and, rarely, gallbladder pseudolithiasis (the formation of “stones” in the gallbladder without true stones).
Hematologic Effects: Ceftriaxone can rarely cause hematologic abnormalities such as eosinophilia, leukopenia, thrombocytopenia, and hemolytic anemia.
Local Reactions: Pain, swelling, and inflammation at the injection site are possible, particularly with intramuscular administration.

Drug Interactions:

Calcium-containing Solutions: Ceftriaxone should not be mixed or administered simultaneously with calcium-containing intravenous solutions (e.g., calcium-containing infusions or parenteral nutrition solutions) in neonates and infants under 28 days of age due to the risk of forming precipitates in the lungs and kidneys.
Anticoagulants (e.g., Warfarin): Ceftriaxone may enhance the anticoagulant effect of Warfarin by displacing it from its protein binding sites, potentially leading to an increased risk of bleeding.
Probenecid: Probenecid may increase the serum concentrations of ceftriaxone by inhibiting renal tubular secretion, prolonging its elimination half-life, and potentially increasing its toxicity.
Calcium-containing Oral Medications: Ceftriaxone can also chelate calcium in the gut, reducing the absorption of oral calcium supplements and other medications that require calcium for absorption (e.g., oral iron supplements, oral tetracycline antibiotics).

As with any medication, it’s crucial to inform your healthcare provider about all medications, supplements, and herbal products you are taking to avoid potential interactions and adverse effects.

Contraindication of ceftriaxone-injection

Ceftriaxone is contraindicated in individuals with a known hypersensitivity to cephalosporins or any component of the formulation. Cross-reactivity with penicillins may occur in patients with a history of penicillin allergy, although this is relatively rare.

How is ceftriaxone administered?

Ceftriaxone is typically administered intravenously (IV) or intramuscularly (IM), depending on the indication and the patient’s condition.

Intravenous (IV) Administration:

Ceftriaxone for IV administration is usually supplied as a powder in vials, which needs to be reconstituted with a compatible diluent, such as sterile water for injection, normal saline (0.9% sodium chloride), or other appropriate solutions.

Intramuscular (IM) Administration:

Ceftriaxone for IM administration is also supplied as a powder in vials, which needs to be reconstituted with a suitable diluent, typically sterile water, for injection.

Intramuscular administration allows for slower absorption compared to IV administration but may be preferred in patients who cannot tolerate IV injections or in settings where IV access is limited.

Regardless of the route of administration, it’s essential to follow the manufacturer’s instructions for reconstitution, dilution, and administration of ceftriaxone to ensure the proper dose is delivered safely and effectively.

Dosing and strength of ceftriaxone

Ceftriaxone dosing varies by age.

Adults: Typically 1-2 grams once daily.
Children: Dose based on weight, usually 50–75 mg/kg once daily.
Neonates: lower doses, around 20–50 mg/kg once daily.

Injectable solution

1 g/50 mL
2 g/50mL

Powder for injection

250 mg
500 mg
1 g
2 g
10 g (adult only)
100 g (adult only)

These are general guidelines, and dosing may vary based on specific indications, the severity of the infection, and individual patient factors. Always consult a healthcare professional for accurate dosing recommendations.