4. Infections
Several bacterial, viral, and yeast infections might cause the lips to become irritated and begin to swell. If you get any type of infection that causes you to become ill, you may notice that your lips become swollen as well. People who have compromised immune systems may also experience swelling in their lips on occasion when their bodies are attempting to fight off any type of infection that they might get.
If you are feeling ill and notice swelling in your lips or any other area of your body, it is a good idea to go to your doctor to find out the underlying cause. Some infections may be cured through the use of antibiotics or other medications. If the infection is viral, you may just have to wait until your body fights off the virus. Your doctor will be able to determine the best course of action for whatever type of infection you might have.