Sebaceous cyst drainage is not as big as before because the contents of the cyst are drained out. A sebaceous cyst is a cystic cavity formed by the long-term accumulation and liquefaction of sebum inside the hair follicle, which collects a large amount of sebum secretion. By incision and drainage, some or all of the cyst contents can be drained out, and the cystic cavity will become smaller, and sebaceous cysts will not be as big as before. However, if the cyst cavity is preserved, the sebaceous cyst may still recur in the later stage, and the sebaceous cyst can be effectively removed by stripping the cyst wall completely through surgery. Pay attention to a light diet, prohibit spicy and stimulating food, drink more water, and do not scratch excessively to avoid causing skin infections, if you feel unwell, it is recommended to go to the relevant departments of the hospital and follow the guidance of a professional doctor, so as to avoid delaying the condition.