Swelling inside the lower lip

The inner lip can swell after biting it, rubbing against a sharp tooth, eating irritating food, or developing a blocked minor salivary gland cyst. A sore, ulcer, dental problem, or local infection may also cause focal swelling. Sudden swelling of the lip, mouth, or nearby tissues can be Angioedema, especially after a new food, medicine, or sting. The timing, pain, surface change, and whether one or both lips are involved help guide assessment.

Avoid the suspected irritant and rinse gently with water. Choose soft, cool foods temporarily and avoid biting or pressing the area. Do not puncture a lump or apply harsh antiseptics inside the mouth. Note when the swelling began, what you ate or took, and any dental treatment or injury around that time. A clinician or dentist can examine a persistent, painful, or recurrent swelling.

Call emergency services immediately for trouble breathing or swallowing, throat or tongue swelling, voice change, wheezing, dizziness, or rapidly worsening facial swelling. Seek prompt medical care for fever, pus, severe pain, spreading redness, or swelling after dental treatment. Arrange an appointment if a lump persists, repeatedly returns, bleeds, or interferes with eating.

Ask whether the swelling looks traumatic, dental, infectious, cystic, or allergic; whether you need dental or medical review; and which changes should prompt emergency action.