Canker sores with pus squeezed out do not necessarily heal. Canker sores are bacterial infections of the hair follicles and surrounding tissues, mostly caused by Staphylococcus aureus. The treatment is to drain the pus out of the canker sores, but it doesn’t mean that it will be good, and it may lead to further aggravation of the infection. It is important not to pinch the carbuncle in special places, such as in the nostrils and upper lip “danger triangle” carbuncle, so as not to cause secondary infection. If there is pus in the carbuncle, it needs to be incised and drained. The doctor will make a “+” or “++” shaped incision in the skin lesion to remove the pus and try to remove the necrotic tissue, and then use gauze to stop the bleeding after finishing the operation. The use of muscle cream to promote the growth of granulation, but the use of patients allergic to muscle cream is prohibited. At the same time, you need to take amoxicillin, cefaclor and other antibiotics to prevent infection, severe infection also need intravenous cefazolin, ciprofloxacin and other antibiotic treatment. For patients with chronic diseases such as diabetes, the need to strictly control the condition. When the patient’s carbuncle has pus, must not be self-treatment, should immediately go to the hospital, please doctor for appropriate treatment.