Best remedy for cold sores: raw honey and turmeric. Dab on as a paste. Use early, use often. See the blog for the science. http://www.thehealthyhomeeconomist.com/effective-home-remedies-for-cold-sores-fever-blisters/
Cold sores are usually caused by an infection but in my experience I get cold sores as a result of stress a cold sore is a small blister that mainly forms around mouth and lips. My sores usually sting and form on the upper lip by my nose.
A herpes infection is caused by the herpes simplex virus (HSV), which comes in two forms: which usually results in oral herpes infections affecting the mouth and lips; and which usually causes genital herpes affecting the genitals and anus.