Efficacy of a standardized herbal formulation from Glycyrrhiza glabra L. as an adjuvant treatment in hospitalized patients with COVID-19: A Randomized Controlled trial

Abstract

IntroductionAs no specific pharmacological intervention has been known for COVID-19, medicinal plants may be a suitable candidate for management of this disease. The aim of this study was to investigate the efficacy of a herbal syrup from licorice as an adjuvant treatment in hospitalized patients with COVID-19. Materials and methods213 hospitalized patients diagnosed with COVID-19 were assigned to receive either standardized licorice syrup as an adjuvant treatment plus standard care [Syrup Group (SYRUP), N = 91], or standard care alone [Standard Group (STANDARD), N = 104], for 7 days. The primary endpoint was duration of hospitalization in survivors. The secondary endpoints included 25% increase in oxygen saturation, C-reactive protein (CRP) difference and lymphocyte difference from baseline, number of death and number of patients transferred to ICU. ResultsMean duration of admission was 5.24 days in SYRUP and 7.14 days in STANDARD (p < 0.001). Oxygen saturation increased in 86 of 91 patients (94.5%) in the licorice group, compared to 83 of 104 patients (79.8%) in the control group (p = 0.002). There was no significant difference between the two groups in the number of patients died during hospitalization (p = 0.837). Five patients in SYRUP and 16 patients in STANDARD were transferred to ICU (p < 0.026). Mean reduction in CRP (p < 0.001) and mean increase in the number of lymphocytes (p = 0.008) in SYRUP were significantly higher than STANDARD. DiscussionLicorice syrup as an adjuvant treatment demonstrated promising results on duration of hospital admission, O2 saturation as well as inflammatory markers in COVID-19 patients; however, further clinical studies with larger sample size are suggested to achieve more conclusive results.