Inclusion Criteria  To be eligible for enrollment, a subject must meet the following criteria:  Understands the requirements of the study and provides written informed consent prior to undergoing any study-related procedures. Subject is a male or female between the ages of 18-65 years old, inclusive. Fitzpatrick skin type II or III. History of at least one year of herpes labialis induced by UV exposure. Able to recall exact location of most common or most recent outbreak. History of at least 50% of cold sore outbreaks occurring with UV (sun) exposure. At least 1 HSV-1 outbreak within the past 12 months. Experiences prodromal symptoms before HSV-1 outbreaks. Subject is willing and able to comply with protocol-specified dosing, visits to the clinic and tracking of pain.  Exclusion Criteria  Subjects will be excluded from the study if they meet any of the following criteria:  Outbreak <2 weeks prior to enrollment. History of herpes simplex vaccine. On antiviral suppression within the past 30 days. Requires more than acetaminophen for pain from recurrent HSV outbreaks. On any systemic or topical steroid, immune suppressant or chemotherapeutic agent within the past 30 days. Use of tanning beds, history of sunburn, or beach vacation <2 weeks prior to enrollment. History of photosensitivity, lupus erythematosus, or current use of photosensitizing medication. Current immunosuppressed state due to underlying disease (i.e. HIV infection) concomitant treatment (i.e. chemotherapy). Current upper respiratory tract infection or any active illness that could trigger cold sores or affect overall health of the patient or the assessment of the study agent. Pregnant or intending to become pregnant during the study. Abnormal skin conditions in the area of the recurrent HSV1 outbreaks. Enrolled in another clinical trial within the past 30 days. Previously treated with EED. On any analgesics or NSAIDs that cannot be stopped during the study. Alcohol or drug abuse.