• Cold sore (fever blister) is a recurrent sore outside the mouth, usually on the edge of the lip.
• Cold sore is usually a painful, burning or stinging ulcer and the discomfort usually begins before the ulcer appears.
• Cold sore is red with raised edges and crusting.
• Cold sore usually recurs at the same location and eruptions of the ulcer are sometimes associated with stress.
• Cold sore is caused by the Herpes simplex virus.
This document is not intended to substitute for professional medical
advice. Do not use this information to diagnose or develop a treatment
plan for a health problem or disease without consulting your physician.
Updated March 1st 2009