Safety evaluation of continuous administration of a high dose of Valeriana fauriei root extract in mice and in humans through an open‐label study

Abstract Aim This study aimed to clarify the safety of Valeriana fauriei root (VF) ethanol extract through in vivo and clinical trials. Methods Mice were divided into VF and control groups. They were given VF (4 g VF/kg/day) or the vehicle mixed in the powdered food for four weeks. Food consumption and body weight changes were evaluated, and blood biochemistry and organ weights were assessed on the last day. In addition, an open‐label study was conducted on healthy subjects who took VF capsules (10 g VF/body/day) for four weeks and were asked to report any changes in their physical condition. Physical, hematologic, blood biochemical examination and urinalysis were performed before, two weeks, and four weeks into the study. Results Food consumption and weight gain in mice did not differ between the VF and control groups, except for experimental error, and there were no particular differences in the weights of the brain, lung, heart, liver, spleen, and kidney. In mice, VF administration resulted in small but significant decreases in albumin in males and females, and total cholesterol and high‐density lipoprotein cholesterol in females only. These levels were unchanged, but daytime sleepiness was observed in humans. Conclusion Since there was little change in the experimental values at continuous high doses of VF at 10 g/day, it can be concluded that approximately one‐fifth of this dose (2 g VF/day) is less harmful. However, daytime sleepiness should be considered.