Syphilis / Latent

Early Latent Syphilis: Benzathine penicillin G 2.4 million units IM in a single dose  

Late Latent Syphilis: Benzathine penicillin G 7.2 million units total, administered as 3 doses of 2.4 million units IM each at 1-week intervals  

Early Latent Syphilis: Benzathine penicillin G 2.4 million units IM in a single dose 

Late Latent Syphilis or Latent Syphilis of Unknown Duration Among Persons with HIV Infection: Benzathine penicillin G 7.2 million units total, administered as 3 doses of 2.4 million units IM at 1-week intervals 

Infants and children aged ≥1 month with diagnosed latent syphilis should be managed by a pediatric infectious disease specialist and receive a CSF examination.  

Pregnant women should be treated with the recommended penicillin regimen for their stage of infection. 

Certain evidence indicates that additional therapy is beneficial for pregnant women to prevent congenital syphilis. For women who have primary, secondary, or early latent syphilis, a second dose of benzathine penicillin G 2.4 million units IM can be administered 1 week after the initial dose.

Latent syphilis can also be vertically transmitted to a fetus; therefore, the goal of treating a pregnant woman is to prevent congenital syphilis. Although clinical experience supports the effectiveness of penicillin in achieving this goal, limited evidence is available for guiding choice of specific regimens or duration.  

Missed doses >9 days between doses are not acceptable for pregnant women receiving therapy for late latent syphilis. An optimal interval between doses is 7 days for pregnant women. If a pregnant woman does not return for the next dose on day 7, every effort should be made to contact her and link her to immediate treatment within 2 days to avoid retreatment. Pregnant women who miss a dose of therapy should repeat the full course of therapy. 

Parenteral penicillin G is the only therapy with documented efficacy for syphilis during pregnancy. Pregnant women who are allergic to penicillin should be desensitized and treated with penicillin G. Skin testing or oral graded penicillin dose challenge might be helpful in identifying women at risk for acute allergic reactions.