Syphilis type	Treatment
Primary and secondary	Penicillin G benzathine, 2.4 million units IM 1 time In people allergic to penicillin: Doxycycline, 100 mg orally 2 times per day for 14 days (preferred)  or Tetracycline, 500 mg orally 4 times per day for 14 days  or Ceftriaxone (Rocephin), 1 to 2 g IM or IV per day for 10 to 14 days*  or Azithromycin (Zithromax), single 2-g oral dose has been effective in some populations†
Early latent	Penicillin G benzathine, 2.4 million units IM 1 time
Late latent or latent of unknown duration	Penicillin G benzathine, 2.4 million units IM at 1-week intervals for 3 weeks
Tertiary	Penicillin G benzathine, 2.4 million units IM at 1-week intervals for 3 weeks
Ocular or neurosyphilis	Aqueous crystalline penicillin G, 18 to 24 million units IV per day, given as 3 to 4 million units every 4 hours or as continuous infusion, for 10 to 14 days Alternative if compliance is ensured: Penicillin G procaine, 2.4 million units IM 1 time per day for 10 to 14 days  plus Probenecid, 500 mg orally 4 times per day for 10 to 14 days
Syphilis during pregnancy	Penicillin regimen appropriate for infection stage (desensitization may be required)
Congenital	Penicillin-based regimen that differs based on probability of infection (as determined by serology and cerebrospinal fluid testing)‡