Antihypertensive Efficacy and Safety of a Standardized Herbal Medicinal Product of Hibiscus Sabdariffa and Olea Europaea Extracts (NW Roselle): A Phase-II, Randomized, Double-blind, Captopril-controlled Clinical Trial

Hypertension is a public health concern that needs immediate attention upon diagnosis. The demand for natural alternatives is on the rise; Hibiscus sabdariffa and Olea europaea are traditionally used for hypertension management in Egypt. In this study, we aimed to investigate the antihypertensive efficacy and safety of two doses of an herbal product of Hibiscus sabdariffa calyxes and Olea europaea leaves (NW Roselle) in Egyptian patients with grade 1 essential hypertension. We equally randomized 134 patients to receive captopril 25 mg, low-dose NW Roselle, or high-dose NW Roselle BID for 8 weeks. No significant decrease was found in systolic blood pressure or diastolic blood pressure when we compared low-dose NW Roselle and high-dose NW Roselle to captopril (p > .05). In all groups, mean reduction in BP at 8 weeks was significant; 16.4/9.9 mmHg (p < .0001), 15.4/9.6 mmHg (p < .0001), and 14.9/9.4 mmHg (p < .0001) with captopril, low-dose NW Roselle, and high-dose NW Roselle respectively. In addition, low-dose NW Roselle induced a significant reduction in the mean level of triglycerides (17.56 mg/dL; p = .038). In conclusion, NW Roselle had comparable antihypertensive efficacy and safety to captopril in Egyptian patients with grade 1 essential hypertension.