Primary syphilis | Benzathine penicillin G | 2.4 million units IM (single dose) |
Secondary syphilis | Benzathine penicillin G | 2.4 million units IM (single dose) |
Early latent syphilis (< 1 y) | Benzathine penicillin G | 2.4 million units IM (single dose) |
Late latent syphilis or latent syphilis of unknown duration | Benzathine penicillin G | 3 doses of 2.4 million units IM each, at 1-wk intervals |
Neurosyphilis or syphilitic eye disease | Aqueous crystalline penicillin G | 18–24 million units/d (3–4 million units IV every 4 h or continuous infusion for 10–14 d) |