A comedo is a sebaceous cyst. Inside a normal cyst is a creamy substance formed by the accumulation of sebaceous gland secretions, not pus, and pus can appear only after an infection occurs. Squeezing a sebaceous cyst to drain the pus is not acceptable. Although the pus may be discharged by squeezing, the cyst envelope inside cannot be removed, and it is easy to recur, so try to treat it surgically.
Sebaceous cysts are susceptible to bacterial infection, abscess formation, or even inflammatory infection resulting in pus coming out of the broken skin, at this time, although squeezing may drain the pus, but the sebaceous cysts of the envelope can not be discharged, and may be relapsed again.
After sebaceous cyst infection, go to the hospital in time. If the abscess is not formed, you can use topical mupirocin ointment, take amoxicillin, cefaclor and other antibiotics to fight infection; if the abscess has been formed, you need to incise and drain the pus, clean the pus cavity after discharging the pus, remove the peritoneum to reduce the chance of recurrence.
After the sebaceous cyst has formed pus, you need to go to the hospital and let the doctor incise and drain to clean the pus cavity. If no infection occurs, it can be removed by elective surgery. Medications should be applied under medical supervision.