Mouth ulcers generally can’t take fire-clearing tablets and three yellow tablets at the same time. Clear fire tablets and three yellow tablets are Chinese medicines, clear fire tablets are mainly used for sore throat, dizziness and other symptoms, three yellow tablets are mainly used for sore throat, thirst and other symptoms, both contain rhubarb ingredients, taking at the same time will be too much, may produce diarrhea, abdominal pain and other symptoms, it is recommended that the doctor’s guidance in the reasonable use of drugs. Patients should pay attention to oral hygiene, clean the mouth 2~3 times a day, ensure sufficient time, avoid overwork, while the diet should be light, warm and soft food, such as steamed eggs, tofu, etc., and avoid spicy and stimulating food, smoking, drinking and so on. It is recommended that patients go to the hospital for examination in a timely manner, under the guidance of the doctor reasonable use of medication, do not self-medication.