Ceftriaxone belongs to the family of antibiotics known as cephalosporins. It is used to prevent or treat certain infections caused by bacteria. It is given by injection only into a muscle or vein. Ceftriaxone is often used to treat infections of the lung, urinary tract, skin, abdomen, bone, joint, and lining of the brain (meningitis), depending on the bacteria causing them. It can also be used to treat gonorrhea (a sexually transmitted infection).