(HealthDay News) -- Cold sores are small, red or purple blisters that usually appear on the lip or corner of the mouth. They often last a week or two, form a crust, then disappear.
Cold sores are commonly triggered by stress, illness, exposure to the sun, or exposure to someone else who has had a cold sore, which is caused by the herpes simplex virus. If around someone who has a cold sore, avoid kissing them, touching their mouth, or sharing drinks or napkins, the Nemours Foundation advises.
Although most cold sores will go away on their own, acetaminophen or aspirin may help alleviate pain or soreness. Try not to touch or pick at the cold sore, as that could slow the healing process and cause the sore to spread.
