Abscesses can be caused purely and simply by bacteria, and then, of course, the cure is to administer antibiotics. Occasionally, though, abscesses are subcutaneous and are not filled with pus but with blood serum; this type clears up pretty quickly on opening. If the abscess is pus-filled, foment it frequently with hot water until the head has turned yellow. The abscess can then be punctured, the pus let out, and an antibiotic cream like penicillin placed on a piece of clean linen or gauze around the wound. Keep the wound open until all infection has subsided.