What Could Cause a Swollen Bump to Appear on My Lip Suddenly?

There are several reasons you might see a bump on your lip. One possibility is that you accidentally hurt your lip by biting it or bumping it. This minor injury can cause swelling as your body works to heal the area. Another cause could be an allergic reaction. An allergy to food, a new cosmetic, or even an insect bite near the lip can trigger your body to swell in the area. Additionally, infections are another cause. Sometimes, viruses—like those that cause cold sores—or bacteria can make a small bump appear as your body fights the infection. A blockage in a minor salivary gland might also lead to a mucocele, which is a harmless, fluid-filled bump that often develops after a small injury. If you find that the bump doesn’t get better, it grows, or you have pain and other symptoms, it’s important to talk with a doctor for further evaluation and care.