Since pus is associated with an infection, the infection is what is dangerous. Left untreated, an infection can cause some severe issues in the long run. Infections are treate
…d with antibiotics, and some require being lanced. Lancing an infection is a procedure in which a scalpel is used by a doctor to open the infection to allow it to drain, and then is often packed with gauze to keep it drained. What drains is the pus and other fluids that don't belong there. Even though it is sometimes a fairly deep wound, a doctor usually doesn't stitch this up until it has had time to drain and it often heals together on its own. ( Full Answer )