The patients will receive an agent with the same vehicle as methylene blue to mimic irrigation with the photosensitizer and the laser will be switched off at the time of application. The placebo PDT procedures will be performed on the lesion: Application of methylene blue placebo with a carpule syringe and needle (with stop and without bevel) inside the lesions; 1 minute of pre-irradiation will be expected. The irradiations will be performed with the same device positioned in the same way and at the same time of application, however, the laser will be turned off. The beep sound will be recorded and turned on during application to blind treatment to the patient. The patient will receive a catheter with acyclovir cream and will be advised to spread on the lesions four times a day for 7 days, which will be their return for reevaluation. It will be washed in abundance with saline (saline solution) until the total removal of the placebo from the photosensitizer.

Patients will be treated with photodynamic therapy and will receive a placebo ointment simulating acyclovir cream. If the lesions are in the vesicle phase, they will be ruptured with a sterile needle. The methylene blue solution at 0.005% concentration will be gently placed on the lesions. Application of methylene blue on the lesions.1 minute of pre-irradiation will be expected. The irradiations will be performed with the Laser Duo® with a wavelength of 660 nm, with a power of 100 mW(milliwatts), the energy density of 300 J / cm², with the energy of 3 J (joules) in the center of the lesion for 30 seconds. The laser will be positioned in direct contact with the lesion, perpendicular, applied centrally to each lesion with energy per point of 3J. Wash in abundance with saline solution until the removal of the photosensitizer is complete. Patients will receive a tube with a placebo cream simulating aciclovir and the same will be advised to spread the cream 4 times per day for 7 days.

Patients will receive Photodynamic Therapy (PDT), irradiations will be performed with the Laser Duo® red laser diode (MMOptics, São Carlos, SP, Brazil) with a wavelength of 660 nm, with a power of 100 mW, the energy density of 300 J / cm², with energy of 3 J in the center of the lesion for 30 seconds. The laser will be positioned in direct contact with the lesion, perpendicular, applied centrally to each isolated lesion that presents with fixed energy per point of 3J. Wash in abundance with saline solution until the removal of the photosensitizer is complete. All treatment proposed in group 1 (simulation of PDT + delivery of aciclovir cream) in each patient will be concluded in a single session. Treatment for group 2 (PDT + placebo cream) will also be completed in a single session. All possible adverse effects will be noted and qualified during the treatment protocol and maintenance period (3/3 months) using the questionnaire developed for this protocol.

Evaluation of the resolution time of the lesions in days (primary objective of the study). For this, a 15-day follow-up will be performed for this variable.The complete resolution will be accompanied by photos and telephone contact and noted in a specific clinical file. For this, a 1-year follow-up will be performed for this variable. The location of the lesions through sextants on the lips (sextants 1, 2 and 3 to upper left to right and sextants 4,5 and 6 from right to left, with sextant 2 in the labial filter region and sextant 5 is its lower lip antagonist.

by qPCR (polymerase reaction ) at the baseline (T0), 3 (T1) and 7 (T2).HSV lesion secretion samples will be collected at 1 single site in the central portion of the lesion with sterile swab after treatment of all HSV lesions. They will be stored in 500 μl of Tris-EDTA (ethylenediamine tetraacetic acid) in tubes of 1 , 5ml for microcentrifuge (Eppendorff®). During the collection period (in the clinic) the samples will be stored on ice inside a styrofoam. These samples will be properly identified and stored at -80ºC (centigrades) (freezer from the UNINOVE University nove de Julho Biophotonics Laboratory) until further analysis.