A. Specific Measures
1. Penicillin - Penicillin, as benzathine penicillin G or aqueous procaine penicillin G, is the drug of choice for all forms of syphilis and other spirochetal infections. Effective tissue levels must be maintained for several days or weeks because of the spirochete’s long generation time (about 30 hours). Penicillin is highly effective in early infections and variably effective in the late stages. The principal contraindication is hypersensitivity to the penicillins. The recommended treatment schedules are included below in the discussion of the various forms of syphilis.
2. Other Antibiotic Therapy - Oral tetracyclines are effective in the treatment of syphilis for patients who are allergic to penicillin. Tetracycline, 500 mg orally four times daily for 14 days, or doxycycline, 100 mg orally twice daily for 14 days, is given for primary, secondary, and early latent syphilis. In syphilis of more than 1 year’s duration or of unknown duration, treatment is continued for 28 days in the same doses.
Preliminary data suggest that both ceftriaxone and azithromycin are effective for the therapy of early syphilis and are now accepted alternative regimens to penicillin after doxycycline and tetracycline. The recommended dose of ceftriaxone is 1 g daily either intramuscularly or intravenously for 8-10 days. Azithromycin can be administered as a single oral dose of 2 g. Recent reports have documented failures of therapy of early syphilis with azithromycin, and this drug should be used only if no alternatives are available. Because of the limited clinical experience with these regimens, close clinical and serologic follow-up is essential. Neither of these regimens has been studied in HIV-positive patients. Ceftriaxone at a higher dose of 2 g daily intramuscularly or intravenously for 10-14 days can also be used as alternative therapy for neurosyphilis in patients with non-immunoglobulin E (IgE)-mediated hypersensitivity to penicillin.
B. Local Measures (Mucocutaneous Lesions)
Local treatment is usually not necessary. No local antiseptics or other chemicals should be applied to a suspected syphilitic lesion until specimens for microscopy have been obtained.
C. Public Health Measures
Patients with infectious syphilis must abstain from sexual activity until rendered noninfectious by antibiotic therapy. All cases of syphilis must be reported to the appropriate public health agency for assistance in identifying and treating contacts. In addition, all patients with syphilis should have an HIV test at the time of diagnosis. In areas of high HIV prevalence, a repeat HIV test should be performed in 3 months if the initial test was negative.
D. Empirical Postexposure Treatment
Patients who have been exposed to infectious syphilis within the preceding 3 months may be infected but seronegative and thus should be treated as for early syphilis. Persons exposed more than 90 days previously should be treated based on serologic results. If their partners are unavailable for testing or unreliable for follow-up, empirical therapy is indicated. Others at high risk either for infection (ie, those with other sexually transmitted diseases and those infected with HIV) or its consequences (ie, pregnant women) should undergo serologic tests for syphilis. The present recommended therapy for gonorrhea (single-dose ceftriaxone or cefpodoxime) may not be effective in treating incubating syphilis. Therefore, patients with gonorrhea and a known exposure to syphilis should be treated with separate regimens effective against both diseases.
- Natural History & Principles of Diagnosis & Treatment
- Laboratory Diagnosis
- Complications of Specific Therapy
- Follow-Up Care
- Course & Prognosis
- Clinical Stages of Syphilis
Revision date: July 6, 2011
Last revised: by Jorge P. Ribeiro, MD