Swelling of the lip can be caused by an allergic reaction or trauma to the area or, in rare cases, as a result of certain diseases such as leukemia or Hodgkin's disease. Once you identify the cause of your swollen lip, you can begin reducing the swelling through at-home treatment. If swelling is a result of a puncture wound to your lip, or if you experience other side effects of an infection, like fever, redness or pus drainage, contact your doctor right away.
Take an over-the-counter antihistamine according to manufacturer's instructions or as recommended by your doctor if you suspect the swelling is the result of an allergic reaction.
Eliminate or avoid any suspected allergens. Dairy, nuts and shellfish are common causes of food allergies. Medication or chemicals in detergents may also cause a reaction.
Clean any cuts on your lip that may cause swelling with a solution of equal parts hydrogen peroxide and water. The solution may foam up as the peroxide reacts to the natural bacteria in your mouth.
Wrap crushed ice cubes inside of a strip of sterile gauze and apply to the swollen area for about 10 minutes each hour.
Ask your doctor about an over-the-counter anti-inflammatory, such as acetaminophen or ibuprofen, to help reduce swelling and control pain.