Effect of Melissa officinalis on systolic and diastolic blood pressures in essential hypertension: A double‐blind crossover clinical trial

For a long time, Melissa officinalis (M. officinalis) has been used to treat cardiovascular diseases. Therefore, this study aimed at evaluating the effects of M. officinalis on systolic and diastolic blood pressures in hypertensive patients. We conducted a double‐blind, controlled, randomized crossover clinical trial on 49 patients who received either M. officinalis capsules (400 mg/d; n = 23) or the placebo (n = 26) three times per day for a 4‐week period. After a 2‐week washout period, the M. officinalis group received placebo and the other group received M. officinalis for another 4‐week period. The systolic and diastolic blood pressures were measured once at baseline and then every 2 weeks for 10 weeks. The statistical analysis of the obtained data revealed that the chronology of the consumption of M. officinalis and placebo had no effect on the systolic and diastolic blood pressures in these two studied groups. Moreover, it was found that systolic and diastolic blood pressures significantly decreased after the consumption of M. officinalis, compared to placebo. Systolic and diastolic blood pressures in group A at the beginning of the study were 152.30 ± 5.312 mmHg and 95.52 ± 1.988 mmHg, respectively, and, after the first phase (drug use), reached 129.88 ± 9.009 mmHg and 80.13 ± 5.488 mmHg, respectively. Systolic and diastolic blood pressures in group B at the beginning of the study was 152.26 ± 5.640 mmHg and 94.44 ± 2.607 mmHg, respectively, and after the second phase (drug use), reached 131.77 ± 8.091 mmHg and 81.46 ± 7.426 mmHg, (p = .005), respectively. Also, no significant side effects were observed during the study. According to the results, M. officinalis can reduce systolic and diastolic blood pressures of the patients with essential hypertension.