Ulcer inside bottom lip

An ulcer inside the lower lip is often caused by minor trauma or an aphthous sore, but a persistent or unusual lesion needs examination.

An oral ulcer is a break in the mucosal lining, often a shallow round or oval sore with a pale centre and red border. Biting, a sharp tooth, an appliance, acidic foods, illness, stress, or some medicines can contribute.

Rinse gently with plain water or salt water, choose soft foods, and avoid spicy, acidic, rough, or very hot items. Do not pick the ulcer, and check for a sharp tooth or denture edge that keeps contacting the lip.

Book an examination if the sore does not heal, returns often, is unusually large, or is hard, numb, bleeding, or accompanied by a neck lump. Urgent care is needed for facial swelling or difficulty breathing or swallowing.

Ask whether the lesion is traumatic, aphthous, infectious, medication-related, or another condition. Ask how to remove a rubbing edge, whether symptom relief is appropriate, and when the area should be reviewed again.