The yellow pus from the periapical infection can be treated with root canal therapy, or antibiotics can be taken to relieve the symptoms. 1. When apical periodontitis occurs, there will be the phenomenon of gum root abscess, when the local pus is too much, there will be the phenomenon of gum breakage and pus flow. If the phenomenon of flowing yellow pus occurs in apical periodontitis, root canal treatment should be carried out in a timely manner to completely remove the infected necrotic material in the root canal, and the phenomenon of flowing yellow pus can be stopped after the infection is controlled. If the pus cannot be completely removed, local incision and drainage can be performed. 2. In addition, if the symptoms of infection are serious, antibiotics such as cefuroxime and metronidazole can be taken to alleviate the symptoms. If the phenomenon of periapical inflammation pus, should go to the hospital in time for examination and treatment, the use of the above drugs need to follow the doctor’s instructions.