**Ceftriaxone**  

**Definition:**  

Ceftriaxone is a third-generation cephalosporin antibiotic widely used for its broad-spectrum activity against bacterial infections. It is a synthetic derivative designed to resist beta-lactamase enzymes, enhancing its effectiveness.  

**Function:**  

Ceftriaxone works by inhibiting bacterial cell wall synthesis, leading to cell lysis and death. It is effective against Gram-positive and Gram-negative bacteria, including strains resistant to other antibiotics. Its long half-life allows for once-daily dosing, making it convenient for clinical use.  

**Applications:**  

Ceftriaxone is commonly used to treat respiratory tract infections, urinary tract infections, meningitis, sepsis, and gonorrhea. It is also utilized in surgical prophylaxis and for managing Lyme disease and other bacterial infections.