Full lips may be popular among Hollywood stars, but for the rest of us, swollen lips can be symptomatic of a problem. Lips usually swell due to trauma or allergies, although some causes are more serious. How quickly a swollen lip heals can indicate the cause of the swelling.
Lips swell when the blood vessels that supply them fill with blood. The structure of the lips includes the thin, delicate skin that covers the outside, and the muscle that lies underneath, which is filled with veins. The final, inner layer of the lips is called the oral mucosa; it forms part of the mucous membrane that lines the mouth. When blood rushes to the lips in response to trauma, allergic reaction or inflammation, this makes the lips swell.
Even minor trauma (such as sports injuries) that doesn't break the skin can cause the lips to swell. Moreover, it's easy to hurt your lips by bumping into things or through other minor accidents. Although the swelling usually subsides without treatment, it can also hide other injuries, like cuts and abrasions that can become inflamed or make chewing and speaking difficult.
Pollen, medications, dyes and certain trigger foods and drinks can cause allergic reactions that include swollen lips. When the body experiences an allergic reaction, it produces histamine. This compound causes the blood vessels in the lips to swell. Other symptoms of an allergic reaction are red, itchy welts known as hives, a swollen or tight throat, breathing difficulties, muscle pain, fever, and rashes or discoloured patches on the feet, genitals, hands or face.
When swollen lips have no obvious cause, they can be symptomatic of a rare condition. The University of Maryland Medical Center lists hereditary angioedema, leukemia and Hodgkin's Disease as a few uncommon causes of swollen lips. The swelling may also be due to MRSA lip cellulitis, as described in a publication of the University of Dentistry and Medicine of New Jersey or granulomatous cheilitis, as mentioned in Clinical Advisor.
Swollen lips often return to normal without treatment. However, if you also experience more serious symptoms, like breathing difficulties or heavy bleeding, seek immediate medical attention. If the swelling continues for more than a few days or is accompanied by pain or fever, you should also visit a doctor, as this may indicate a lip problem. Furthermore, see a doctor if the swelling has no clear cause or if it comes and goes for no apparent reason.
In less serious cases, you can use home treatments to help the swelling go down. When a mild allergic reaction is causing the swollen lip, it should be over within four days, especially if you use over-the-counter antihistamines. For minor cuts and abrasions inside the mouth, ask your dentist or doctor to recommend a mouthwash that facilitates healing, alleviates discomfort, and cleans the mouth.
Swollen lips are usually more inconvenient than serious, but if you have other, more severe symptoms, see a doctor right away. An allergic reaction can quickly turn life-threatening, and serious swelling can also be a sign of another harmful medical condition. In most cases, placing ice on the injury and keeping the area clean should heal your lips in no time.