What causes swollen lips?

There are several reasons why your lips might swell. One common cause is an allergic reaction. This happens when your body reacts strongly to something like food, medication, or an insect bite. Your body makes chemicals that cause swelling, and your lips can become puffy and red. Sometimes, a swelling could be due to an infection. In one study, a rare abscess was found on the lower lip, which means a group of bacteria can cause an infection that makes the area swell up. Another possibility is when you hurt your lip from trauma, like accidentally bumping into something, which causes the body to send extra fluid and white blood cells to the area to help heal. In some cases, other medical conditions or unusual reactions can also make your lips swell. If you notice a swollen lip and feel uncomfortable, you can use this free symptom checker to help identify what might be causing your symptoms and determine whether you should seek medical care.