Ceftriaxone injection is used to treat certain infections caused by bacteria such as gonorrhea (a sexually transmitted disease), pelvic inflammatory disease (infection of the female reproductive organs that may cause infertility), meningitis (infection of the membranes that surround the brain and spinal cord), and infections of the lungs, ears, skin, urinary tract, blood, bones, joints, and abdomen. Ceftriaxone injection is also sometimes given before certain types of surgery to prevent infections that may develop after the operation. Ceftriaxone injection is in a class of medications called cephalosporin antibiotics. It works by killing bacteria. Antibiotics such as ceftriaxone injection will not work for colds, flu, or other viral infections.Using antibiotics when they are not needed increases your risk of getting an infection later that resists antibiotic treatment.