If the exudate is clear mucus, the possibility of glandular labyrinthitis needs to be considered. In addition to swelling of the lips with clear fluid exudation, there can be manifestations such as lower lip ectropion and small nodules can be felt on the lips.
If pus is oozing, then a canker sore or syphilitic chancre may be considered. The canker sore may also be associated with mucosal ectropion and may have a purplish-red centre, along with systemic symptoms such as headache, chills, high fever and loss of appetite. The swelling of the lips in syphilitic chancre can form a giant lip with significant lymph node enlargement.