For many people, symptoms are more severe the first time they develop a cold sore. When you have a cold sore outbreak:
- The first sign of a cold sore is usually a tingling, burning, or itching sensation on or around the lips, beginning about 12-24 hours before the cold sore develops.
- The area becomes red, swollen and painful as the blisters form.
- Over 2-3 days, the blisters rupture and ooze fluid that is clear or slightly yellow. This is sometimes called the “weeping phase.”
- About 4-5 days after the cold sore appears, it crusts and scabs over. It might crack or bleed as it heals.
- The scab then falls off, revealing skin that may be a little more pink or reddish than usual for a few days. It usually takes 1-2 weeks for the cold sore to heal completely.