From the Guidelines
The treatment for confirmed syphilis is primarily penicillin G, with the specific regimen depending on the stage of infection. For primary, secondary, or early latent syphilis (less than one year duration), a single intramuscular injection of benzathine penicillin G 2.4 million units is the recommended treatment, as stated in the guidelines 1. For late latent syphilis (more than one year duration) or syphilis of unknown duration, the recommended regimen is benzathine penicillin G 2.4 million units intramuscularly once weekly for three consecutive weeks. Neurosyphilis, ocular syphilis, or otosyphilis requires more intensive treatment with aqueous crystalline penicillin G 3-4 million units intravenously every 4 hours for 10-14 days. Some key points to consider in the treatment of syphilis include:
- The use of penicillin as the first-line treatment due to its effectiveness against Treponema pallidum 1
- The importance of desensitization to penicillin for pregnant women who are allergic to penicillin 1
- The need for close follow-up and serologic testing to ensure adequate treatment response 1
- The potential for a Jarisch-Herxheimer reaction, a self-limited inflammatory response that may occur within 24 hours of treatment 1 For penicillin-allergic patients, doxycycline 100 mg orally twice daily for 14 days (early syphilis) or 28 days (late syphilis) can be used, though desensitization to penicillin is preferred for pregnant women 1. It's also important to note that the treatment guidelines may vary depending on the specific circumstances of the patient, such as pregnancy or penicillin allergy, and that the most recent and highest quality studies should be consulted to inform treatment decisions 1.
From the FDA Drug Label
Syphilis–early: Patients who are allergic to penicillin should be treated with doxycycline 100 mg, by mouth, twice a day for 2 weeks Syphilis of more than one year’s duration: Patients who are allergic to penicillin should be treated with doxycycline 100 mg, by mouth, twice a day for 4 weeks.
The treatment for a patient with positive Treponema pallidum (TP) antibodies and confirmed syphilis is doxycycline 100 mg, by mouth, twice a day for 2 weeks for early syphilis or 4 weeks for syphilis of more than one year’s duration, in patients who are allergic to penicillin 2.
- Doxycycline is an alternative treatment for syphilis in patients who are allergic to penicillin.
- The dosage and duration of treatment depend on the stage of syphilis.
- It is essential to follow the recommended treatment guidelines to ensure effective treatment and prevent complications.
From the Research
Treatment for Syphilis
The treatment for a patient with positive Treponema pallidum (TP) antibodies and confirmed syphilis is typically benzathine penicillin G 3, 4.
- A single intramuscular dose of benzathine penicillin G is the preferred treatment option for syphilis 4.
- Other β-lactams may be equally or more effective at targeting the disease-causing agent, Treponema pallidum, and have been identified through high-throughput screening 4.
Diagnosis and Testing
The diagnosis of syphilis typically involves serological tests, including:
- Treponema pallidum particle agglutination assay (TPPA) 3, 5, 6
- Rapid plasma reagin (RPR) test 3, 5, 6
- Fluorescent treponemal antibody-absorption (FTA-ABS) assay 5
- TP-specific enzyme-linked immunosorbent assay (TP-ELISA) 6
- TP-specific chemiluminescent immunoassay (TP-CMIA) 6
- These tests can be used to detect Treponema pallidum antibodies and confirm the diagnosis of syphilis.
Treatment Response
The response to treatment can be assessed using non-treponemal tests, such as RPR and TRUST, which can show a decrease in titers after treatment 6.
- Treponemal tests, such as TPPA, TP-ELISA, and TP-CMIA, are recommended for clinical routine screening of syphilis, but may not show a significant decrease in positive rate after treatment 6.