Azithromycin belongs to the second-line drugs in the treatment of syphilis, and its dosage should be decided according to the degree of the disease and so on, there is no uniform dosage, and it is recommended that the patient consults the doctor after use. Syphilis is a sexually transmitted disease caused by syphilis spirochete infection, its drug treatment, preferred intramuscular injection or intravenous drip penicillin, such as intramuscular injection of benzylpenicillin. If the penicillin is allergic, you can choose ceftriaxone, ceftriaxone is also a kind of efficient drug to kill syphilis spirochetes. If the patient is allergic to all of these drugs, azithromycin can be chosen instead, but it is not as effective as penicillin in treating syphilis. When using azithromycin to treat syphilis, it can be given through intravenous drip or orally, so the exact dosage is also related to the route of administration. Syphilis patients are advised to choose the appropriate medication for treatment under the guidance of a professional doctor. If patients are allergic to penicillin and cephalosporin, the dosage of azithromycin should be used after consulting a doctor and following the doctor’s instructions.