Cold sores form clusters of fluid-filled blisters that often burst and ooze. Pimples on the lip line are red bumps with whiteheads, not blisters. Cold sores are contagious, but pimples are not. Cold ...

Cold, dry weather can cause lip irritation, cracking, and cold sores. Blistex offers several over-the-counter products to treat cold sores and moisturize lips. Using antiviral creams at the first sign ...