Recurrent herpes labialis (RHL) is a common recurrent infective vesiculoulcerative disease. Topical and systemic administration of Zinc compounds has been indicated to have preventive and therapeutic effects. The purpose of this study was to evaluate the serum level of zinc in the patients with RHL and healthy individuals and also to investigate the correlation of this level with various parameters of the patient and disease course.

This cross-sectional study was performed on 43 patients with a history of recurrent herpers labialis and 42 subjects without any previous experience of the lesion. Blood samples were taken, and serum zinc level was measured using colorimetry (spectrophotometry) method. Chi-Square test was used to compare the qualitative relationships, and for comparing the quantitative relationships, independent T-test was used. To observe the relationship of quantitative factors including serum zinc level, the number of relapses, and recovery rates, correlation test was taken.

The results show that, serum zinc level has no significant difference between healthy subjects and the patients (p > 0.05). Also, zinc level was not related to age and sex factors and frequency of relapse (p > 0.05). However surprisingly, there was a significant relationship between zinc level and recovery period in the RHL patients. The lower the serum zinc level, the higher the duration of recovery (p = 0.009).

The results of this study indicate that, zinc deficiency can be considered as a risk factor for increasing the duration of herpes labialis lesions. Therefore, the evaluation of serum zinc level in the subjects with RHL and subsequent administration of zinc are recommended in these kind of patients.