Excessive Intake of Long Pepper Extract: Safety Evaluation in Healthy Japanese Adults A Randomized Double-Blind Placebo-Controlled Parallel-Group Trial

摘要

The objective of this study was to investigate the safety of excessive oral intake of long pepper extract (LPE: 750 mg/day;150 mg/tablet x 5 tablets) in healthy volunteers. A randomized double-blind placebo-controlled parallel-group trial was conducted in 52 healthy volunteers (24 males and 28 females) to evaluate the safety of excessive LPE intake. Volunteers were randomly assigned to two groups and given either 750 mg/day of LPE or placebo for 4 weeks. Body weight, body mass index (BMI), pulse, blood and urine parameters, and subjective symptoms were recorded throughout the study and 2 weeks after the study. This trial was registered at UMIN-Clinical Trials Registry as IJMIN000030591. The primary outcome was the incidence of adverse events, as obtained from clinical interviews and daybooks. The secondary outcome was any other clinical parameter. The incidence of adverse events according to clinical interviews and daybooks was 29.2 % for the placebo group and12 % for the LPE group: there were no significant differences between groups for individual events. No clinically concerning changes in body weight, BMT, pulse, blood pressure, and blood and urine parameters were observed between the LPE and placebo groups throughout the study. All parameters of the test sample group were within the range of physiological fluctuation and no adverse effects attributable to LPE intake were observed. The results indicated that daily LPE consumption was safe for healthy adults.