Early syphilis (primary secondary、early latent） in patients allergic to penicillin tetracycline (or erythromycin) 500 mg qid for 15 days doxycyline 100 mg bid for 15 daysEarly syphilis (primary、 secondary、early latent ) • in patients allergic to penicillin - tetracycline (or erythromycin) 500 mg qid for 15 days - doxycyline 100 mg bid for 15 days