Comparison of the topical effectiveness of ST. john's wort (hypericum perforatum L.) oil with olive oil in cases diagnosed with mild plaque type psoriasis vulgaris

This study was conducted as a single-blind randomized controlled experimental study to evaluate the effect of St. John's Wort (Hypericum perforatum L.) oil on healing and the ability to control the disease in patients with mild plaque-type psoriasis vulgaris. The study was conducted with patients who applied to the Dermatology outpatient clinic of Bezmialem Vakıf University Faculty of Medicine Hospital between November 2023 and May 2024. A total of 38 patients were included in the study, and 19 patients were randomly assigned to the experimental group and 19 to the control group. St. John's wort oil was applied to the psoriasis plaques of the patients in the experimental group, and olive oil was applied to the psoriasis plaques of the patients in the control group. The amount of hypericin in the St. John's wort oil used was determined by UV spectrometry (0.076 mg/mL). PASI (Psoriasis Area Severity Index) was used to determine the severity of the disease. Accordingly, erythema, induration and squamation scores of the psoriasis plaques were evaluated before and after treatment. The obtained data were analyzed with the SPSS program. When the changes in the PASI scores (area, erythema, induration, squama) in patients using St. John's Wort oil were examined, the plaques of 13 patients were evaluated and a decrease in the scores was observed. When the pre- and post-study PASI scores of the patients in the experimental and control groups were compared in our study, no significant difference was found in those using olive oil (p=0.779), while a significant difference was found in those using St. John's Wort oil (p=0.016). This showed that St. John's Wort oil had a positive effect on the improvement and control of the disease in patients with mild plaque psoriasis. As a result, it can be recommended that dermatologists prescribe St. John's Wort oil as an adjuvant treatment for outpatient clinic patients. It can be recommended that the products approved by the Ministry of Health of St. John's Wort oil, which has a widespread traditional use, be promoted and that new evidence be presented by conducting research with its different formulations (cream, ointment, etc.). Keywords: Psoriasis vulgaris, PASI, St. John's Wort oil, Hypericum perforatum, hypericin