Canker sores are not recommended to be squeezed. Canker sores are caused by bacterial infection of the skin follicles and are commonly found on the head, back, armpits and buttocks, and are accompanied by a burning and painful sensation. They need anti-infective treatment, and if abscesses appear, they can be treated with surgical incision and drainage of pus, and regular medication changes. If the canker sore is in the stage of whiteheads or blackheads, you can go to the hospital and ask your doctor to make a surgical incision to drain the pus, place drainage strips, and treat it with regular medication changes. Squeezing canker sores accelerates the further spread of inflammation into the surrounding tissues, worsening the inflammation and the risk of bacteremia or sepsis. For canker sores on the face, squeezing to drain the pus is absolutely prohibited because squeezing of the canker sore in this area can lead to sieve sinus infections, which in turn can lead to intracranial infections. Canker sores must continue to take antibiotics such as amoxicillin and cefaclor to prevent infection during recovery.