A rise in titer after a course of syphilis treatment may be normal or may be due to poor treatment, reinfection and other abnormal reasons, it is recommended to follow the doctor’s advice to continue to observe the treatment. 1. Normal phenomenon: It takes some time for the titer of non-syphilis antibody to change after treatment, if the antibody titer test is conducted within two weeks of treatment, some patients may experience a short-term increase in titer, which is not related to the efficacy of the treatment, but is a normal phenomenon. It is normal for the titer to rise less than 4 times after treatment. 2. Abnormal reasons: Syphilis treatment requires early and adequate dosage of medication, poor patient compliance with medication, drug resistance and other reasons can lead to poor efficacy, titer increase. Reinfection due to high-risk sexual behavior during the treatment period can lead to an increase in titer. To sum up, there are many reasons for the titer to rise, it is recommended to consult a professional doctor to analyze the reasons according to the specific situation and follow the doctor’s instructions to use the full amount of standard medication to continue to observe the treatment.