It is very common for lips to swell due to irritation from a nearby pimple, according to the Heal Cure website. This swelling could be caused by physical aggravation of the pimple, such as biting or attempting to pop it, or it could be caused by cystic acne in the area surrounding the lips.
Pimples around the lips can be very painful and cause a lot of irritation. When experiencing any sort of blemish on or around the lips, it is important to determine whether the blemish is in fact a simple pimple or if it could be a cold sore, according to the Med-Health website. Cold sores are caused by the herpes simplex virus, and are often accompanied by swelling and itching sensations in the mouth or nose; they are a more serious issue than pimples and may require medication to heal, according to Teens Health.
If a lip is swollen due to irritation of a nearby pimple, stop aggravating the pimple, advises the Heal Cure website. To reduce swelling of the lips, press a warm towel up against the swollen lip and compress it. To prevent lip swelling from pimples in the future, make sure the skin around the lips is clean and, if necessary, use pimple care products such as daily cleansing pads, as suggested by Heal Cure.