Penicillin allergy can be treated with medications such as ceftriaxone sodium, azithromycin, doxycycline, and erythromycin for syphilis. Syphilis is an infectious disease caused by the syphilis spirochete, and adults are mainly infected through unclean sex. The proliferation of syphilis spirochetes is rapid, and clinically it requires early, adequate, standardized, and full course of treatment. Incomplete treatment may lead to syphilis spirochetes entering the latent stage, resulting in late-stage syphilis. Syphilis spirochetes are sensitive to penicillin, so the clinic usually takes penicillin as the first choice of medicine for the treatment of syphilis, such as benzylpenicillin, procaine penicillin, etc. If the patient has a penicillin allergy, other antibiotics can be used for the treatment, such as ceftriaxone sodium, azithromycin, doxycycline, erythromycin and so on. The dosage of drugs in the treatment of syphilis must be enough, the medication must be standardized, after scientific and reasonable treatment, generally can be completely eradicated. It is recommended to follow the doctor’s instructions for follow-up treatment.