Potential deleterious effects of promoting the use of ceftriaxone in the treatment of Neisseria gonorrhoeae.

BACKGROUND: US gonorrhea treatment guidelines recently changed to promote ceftriaxone as first-line therapy. Because ceftriaxone requires intramuscular administration, this could lead some patients to go untreated.

METHODS: We used an arithmetic model to compare the number of persons with gonorrhea who would be successfully treated with continued use of oral therapies versus exclusive use of ceftriaxone. Our base case scenario assumed the following: decreased cefixime susceptibility in 2% of heterosexuals and 5% of men who have sex with men, baseline oral therapy in 30% of heterosexuals and 15% of men who have sex with men, oral treatment failure in 10% of decreased susceptibility cases, and baseline patient-delivered partner therapy use in 30% of heterosexuals.

RESULTS: Considering only effects on index cases, universal ceftriaxone use would result in fewer cures if at least 5% of oral therapy recipients go untreated with the change in treatment practice. Exclusive ceftriaxone use consistently led to fewer infected persons being cured when the model incorporated partner treatment effects and assumed that the change in treatment practices eliminated the use of patient delivered partner therapy. If oral treatment were 75% effective against decreased susceptibility gonorrhea, exclusive ceftriaxone use would likely increase cure rates in persons with decreased susceptibility gonorrhea, but could diminish them in persons with gonorrhea overall.

CONCLUSIONS: At least in the short term, eliminating oral therapy for gonorrhea will likely have small effects on decreased susceptibility treatment failures and could increase gonorrhea rates overall.