Blood in the saliva after waking up from sleep is usually caused by periodontal disease. Usually, there is a large amount of calculus and plaque around the gums, which will produce the symptoms of bleeding gums and heavier bleeding from brushing teeth. Usually, bleeding tends to occur in the early morning in the second half of the night, and there will be blood in the spit, which can be improved by simply removing the calculus in the mouth. By using ultrasonic scaling and subgingival scraping to remove calculus and rinse it locally, and then applying iodine glycerin or minocycline hydrochloride, the gums can be promoted to adhere to the tooth surface, and the gums will not bleed anymore. It is also recommended to use appropriate mouthwash, such as compound tinidazole solution, compound boric acid solution or compound chlorhexidine rinse.