A boil is the common name for a “boil”, which is an acute purulent inflammation of a single hair follicle and surrounding tissue, most often caused by Staphylococcus aureus infection. Boils have two main phases, the red and swollen phase and the pus thrombosis phase. The erythematous stage can be treated with hot compresses, topical ichthyol ointment, mupirocin ointment, etc. The inflammation of the boil may subside on its own or a yellowish-white pus embolus may appear, i.e., it enters the stage of pus embolism. When pus plugs appear in boils with fluctuating sensation, the lesion can be sterilized with iodophor first, and then the tip of knife or the needle of fine needle can be used to pick up the skin to remove the pus plugs, and after removing the surrounding pus, the pus can be drained with iodophor-oil gauze, and the medication can be changed regularly. Note that it is contraindicated to squeeze the boil to drain the pus, squeezing is likely to lead to the spread of germs, especially within the dangerous triangle from the root of the nose to the corners of the mouth on both sides of the face, squeezing may lead to retrograde infection of pathogenic germs into the skull, resulting in cavernous sinus thrombophlebitis.