The efficacy of olive leaf extract on healing herpes simplex virus labialis: A randomized double-blind study

Herpes simplex virus (HSV), as a common infection in healthy individuals, is treated symptomatically, but drug resistance and the side effects of drugs have drawn the attention of researchers to complementary medicine. Olive Leaf Extract (OLE) has antiviral effects that may treat HSV. The current study aimed to compare the clinical effects of OLE and Acyclovir on HSV-1.

This randomized double-blind clinical trial was conducted on 66 patients who had already been diagnosed with HSV-1. The participants were randomized into two groups, receiving 2% OLE cream or 5% acyclovir cream five times a day for six days. The symptoms were evaluated before, and three and six days after the interventions. Data were analyzed using the SPSS software through the Kolmogorov-Smirnov test, chi-squared, t-test, and repeated measures ANOVA.

The results showed clinical symptoms decreased in both groups during the study and both medications were effective in the treatment of HSV-1. However, the OLE group experienced less bleeding (P = 0.038), itching (P = 0.002), and pain (P = 0.001) on the third day as well as less irritation (P = 0.012), itching (P = 0.003) and color change (P = 0.001) on the sixth day compared to the acyclovir group. The treatment course for participants in the OLE group was shorter than in the acyclovir group (P = 0.001).

The evidence from these trials suggests the OLE cream is superior in the healing of episodes of HSV-1 over the acyclovir cream. Future studies are recommended to investigate if OLE could be an adjunct to acyclovir treatment.