Data on treatment of patients with syphilis were reviewed in preparati
on for revision of the Sexually Transmitted Disease Treatment Guidelin
es of the Centers for Disease Control and Prevention. Published studie
s of treatment regimens available and practical for use today were rev
iewed, particularly in regard to the following issues: treatment for p
rimary, secondary, and latent stages of syphilis; treatment for syphil
is during pregnancy; treatment for syphilis in human immunodeficiency
virus (HIV)-infected patients; and serological criteria for evaluating
response to treatment. The results of treatment and the methodologica
l quality of the studies was considered. Most treatment recommendation
s must be based on expert judgment and with reliance on the clinical e
xperience over 4 decades. For the treatment of early syphilis in HIV-u
ninfected patients, this is probably sufficient. Data about HIV-infect
ed patients are insufficient both for determining whether current ther
apy is adequate and for recommendation of an alternative if a change i
n therapy is deemed necessary.