Cold sores, also called fever blisters, are a painful infection usually caused by the herpes simplex virus type 1, which can be transmitted through kissing or sharing utensils, towels, or razors with somebody who is infected. The sores may show up anywhere on the body, but typically appear on the gums, the outside of the mouth and lips, the nose, cheeks, or fingers. The sores usually last seven to 10 days and are contagious. There is no cure for cold sores, but the pain can be alleviated by avoiding spicy or acidic foods, applying ice, and using over-the-counter numbing remedies. Antiviral drugs may also be used to treat cold sores. Follow the links below to find WebMD's comprehensive coverage about how cold sores are contracted, how they are diagnosed, how they are treated, and much more.