Background/Objectives: Primary insomnia is characterized by persistent sleeplessness that is not caused by medical, psychological, or environmental factors. It is defined by difficulty initiating or maintaining sleep for at least one month, leading to significant distress or impairment in daily functioning. This randomized, crossover, double-blind, placebo-controlled clinical trial aimed to assess the efficacy and tolerability of a Scutellaria lateriflora L. extract-based food supplement in subjects with mild to moderate primary insomnia. Methods: A total of 66 participants, aged 18-70 years, were randomly allocated into two groups (1:1 allocation ratio) and received either the food supplement (400 mg/day) or a placebo for 56 days, separated by a 28-day washout period. The clinical effectiveness of the food supplement was assessed using the Pittsburgh Sleep Quality Index (PSQI) as the primary outcome measure. Secondary outcomes included sleep-wake cycle parameters (sleep onset latency, sleep efficiency, and total sleep time) and a Visual Analog Scale (VAS). Results: A significant improvement in sleep-wake balance following supplementation with S. lateriflora, as reflected by enhanced scores in both primary and secondary outcomes, was observed. Furthermore, none of the participants reported adverse effects from the food supplement. Conclusions: Overall, these findings suggest that a S. lateriflora extract-based food supplement is a safe and effective strategy for restoring the sleep-wake cycle and improving quality of life in individuals with primary insomnia.
Keywords: Scutellaria lateriflora L.; primary insomnia; randomized clinical trial; sleep efficiency; sleep quality; sleep-wake cycle.