Third-stage syphilis is the most severe stage of the disease. It generally damages the nervous system and cardiovascular system of the human body, thus having a significant impact. There is no definite timeline for the cure of third-stage syphilis. The treatment of third-stage syphilis primarily involves controlling the condition with medication; there is still no specific method that can completely cure it thoroughly. Therefore, it is necessary to take medication for a long period. Currently, for treating third-stage syphilis, procaine penicillin is generally chosen for patients. In fact, procaine penicillin mainly helps effectively control the syphilis spirochete.