Syphilis | Stages, Symptoms, Treatment & Prevention

2- Late latent syphilis (more than one year) and syphilis of unknown duration:

The CDC recommends “benzathine penicillin G” 3 doses intramuscularly (2.4 million units each) every week.

In case of penicillin allergy, CDC recommends “doxycycline” twice daily orally (100 mg) for 30 days.