What should you know about very swollen lip?

Lip swelling may follow a bite, injury, sun exposure, contact with a cosmetic, dental work, a medicine or an infection. Sudden swelling of the lips is a common presentation of angioedema, a deeper swelling reaction that may occur with or without hives. The timing and associated symptoms help a clinician distinguish these possibilities.

Note what happened before the swelling began, including new foods, medicines, skincare, lip products or procedures. Avoid assuming that a new product is harmless simply because it was used only once.

Stop using any newly introduced lip or oral product and avoid rubbing or picking the area. A cool, clean compress may ease discomfort. Do not take a medicine specifically for the swelling unless a clinician or pharmacist has advised that it is appropriate for you.

If the swelling is mild and stable, arrange medical advice to identify the cause, particularly when it recurs. Take a photograph and note its onset, possible triggers and whether hives, itching, pain or fever appeared.

Call emergency services immediately if lip swelling is accompanied by tongue or throat swelling, hoarse voice, trouble breathing, wheezing, difficulty swallowing, dizziness or collapse. Seek prompt medical assessment for rapidly increasing swelling, severe pain, spreading redness, pus or fever. Recurrent episodes also deserve review, even if they settle.

Ask whether the episode could be angioedema, an infection, irritation or another cause. Discuss which triggers to avoid, what symptoms should prompt emergency action, and whether you need a written plan for a future episode.