Ceftriaxone is a third-generation cephalosporin with antibacterial and pharmacokinetic characteristics that make it an excellent choice for the treatment of gonococcal infection and chancroid. Adverse effects are unusual. Clinical efficacy in all reported studies has been excellent. Additional studies are required for further elucidation of the role of ceftriaxone in the treatment of pelvic inflammatory disease and syphilis. Chlamydial infections are not altered by ceftriaxone, and additional treatment is necessary if Chlamydia is present concurrently with Neisseria gonorrhoeae.