Causes of a swollen lower lip

A small, tender area may follow biting the lip, friction, a burn, or an insect bite. Itching, hives, or swelling elsewhere can occur with angioedema or another allergic reaction. Increasing warmth, redness, pus, fever, or tooth or gum pain needs assessment for infection. A blister or grouped sores may have a viral cause. A firm spot that remains after the swelling settles should also be examined. Lower-lip location alone does not identify the cause.

Use a cool wrapped compress and keep the area clean. Avoid chewing the swollen area, harsh mouth products, smoking, and foods that sting. Stop a newly introduced lip product and note any recent food, medicine, dental work, bite, or injury. Do not pop blisters or drain a lump. Arrange review when swelling persists, returns, or is accompanied by pain or fever. Related reading: [Angioedema](/conditions/angioedema/).

Call emergency services for breathing difficulty, throat or tongue swelling, trouble swallowing, voice change, faintness, or rapidly worsening facial swelling. Seek prompt care for fever, severe dental pain, spreading redness, pus, severe pain, or swelling that involves the eye. A rapidly enlarging lump or swelling after a serious injury also needs urgent evaluation.

Does the location and tenderness suggest injury, irritation, infection, or angioedema? Could a tooth or gum problem be contributing? Should I stop any medicine or oral-care product? What should I do if the swelling returns or spreads?