The purpose of this work was to study the effect of laser therapy on the healing and relapse rate of patients with labial herpes simplex infections. 232 patients with herpes simplex were selected for either laser therapy or antiviral medication (acyclovir). Patients in the laser group received approximately 2 Joules per blister in the early onset stage and 5 Joules in the later stages plus 1 Joule at the C2-C3 vertebrae. In a consecutive study, 322 patients receiving laser therapy were followed during 5 years to observe the period of occurrences!  An obvious effect of laser therapy was found for both initial healing and for the length of the recurrence periods. These two well controlled and long term studies confirm that laser therapy is an effective treatment modality for herpes without any observed side effects.

Photomed Laser Surg. 2011 Nov 2. The Effect of 670-nm Low Laser Therapy on Herpes Simplex Type 1.Muñoz Sanchez PJ, et al.