Effects of the Pistacia atlantica subsp. kurdica Oleoresin on The Symptoms and Quality of Life in Functional Dyspepsia: A Randomized Controlled Trial

The Pistacia atlantica subsp. kurdica oleoresin (OPA) is utilized for the treatment of dyspepsia and other gastrointestinal diseases in the Persian Medicine. Therefore, the therapeutic efficacy and safety of standardized OPA in functional dyspepsia (FD) were evaluated. To standardize OPA, the constituents of the OPA essential oil were determined by gas chromatography-mass spectrometry. Fifty patients were allocated to each of the OPA and placebo groups. The OPA and placebo groups consumed two 200 mg OPA or placebo capsules, respectively, every 12 hours along with one 40 mg famotidine tablet per day for 8 weeks. Dyspepsia severity was the primary outcome measured by the Hong Kong dyspepsia index. The secondary outcomes included quality of life measured by the sf-36 questionnaire, complete blood count, and the blood levels of alanine aminotransferase, aspartate aminotransferase, blood urea nitrogen, creatinine, triglyceride, total cholesterol, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol. The outcomes were measured at the baseline and endpoint. OPA contained 10% w/w essential oil, and the constituents of the OPA essential oil were α-pinene (96%), β- pinene (2%) and terpinolene (2%). Thirty five patients in each group completed the trial. OPA decreased the Hong Kong score significantly (p = 0.013), but the placebo had no significant effect on the Hong Kong score (p = 0.651), at the endpoint compared to baseline. The sf-36 questionnaire score of the OPA group increased significantly (p = 0.027), but it increased insignificantly in the placebo group (p = 0.078), at the endpoint compared to baseline. There was no significant effect on the blood tests, and also no side effect. Thus, OPA may mitigate the symptoms, and increase the quality of life of the FD patients without side effects. The OPA essential oil and the monoterpenes α-pinene, β- pinene and terpinolene may be responsible for the effects of OPA in FD.