Genital herpes is a common and increasingly-common infection worldwide. The annual incidence in the United States is 1.75 per 1000 inhabitants. The etiologic agent is the herpes type 1 and 2 strains simplex virus. Classical Treatment is with acyclovir which decreases the duration of the disease and prevents rashes but has no curative effect. Also, studies show herpes resistance to acyclovir which has stimulating research into new drugs to treat this condition. Authors suggest melatonin way be a therapeutic agent in herpetic disease due to its modulatory action in immune and inflammatory responses when administered in adequate doses. Therefore, the aim of this study is to evaluate the effects of melatonin in the treatment of genital herpes as well as compare it to acyclovir in a double-blind, prospective and randomized, investigation. Outcome measures will include clinical evaluation of patients and laboratory endpoints.

The authors have investigate the relationship of estrogen-dependent malignant tumors with reduced levels of melatonin. It is speculated that the indoleamine can be classified as anti-estrogenic drug, both by its action on estrogen synthesis with aromatase inhibition and by its interference with estrogen receptors. Experimentally melatonin prevents promotion and growth of mammary tumors in rodents, probably by interacting with epithelial cell receptor; increasing local immunity by acting as an antioxidant agent and by inhibiting telomerase activity in tumor cells .

Inclusion criteria:

• clinical and laboratory diagnosis of genital herpes
• real time polymerase chain reaction for herpes type 2
• serology

Exclusion criteria:

• immunodeficiencies
• pregnant women

Female only

The patients will be treated at the Clinic of Gynecology, University of Sao Paulo during a total of 04 visits. In the first and fourth visits, patients will be sent to the laboratory of the University Hospital for collecting the cluster of differentiation 4 cells, interleukin-2 and serology for herpes.