This study published in 2020 is a double-blind randomised placebo control study which assessed efficacy of passionflower extracts (60mg and 80% leaves, 20% fruit) vs placebo nightly for two weeks on patients suffering from insomnia. After two weeks sleep quality was assessed using polysomnography for total sleep duration, sleep efficacy, sleep latency, total arousal and wake after sleep onset. Subjective assessments using the Insomnia Severity Index (ISI) and Pittsburgh sleep quality Index (PSQI) were also completed after two weeks. Results found that 84 participants completed the trial (treatment=49 and placebo=45) with no adverse events reported in either group. The passionflower group had improvements in polysmnographic sleep parameter, total sleep time above those in the placebo groups.
Lee J, Jung HY, Lee SI, Choi JH, Kim SG. Effects of Passiflora incarnata Linnaeus on polysomnographic sleep parameters in subjects with insomnia disorder: a double-blind randomized placebo-controlled study. Int Clin Psychopharmacol. 2020;35(1):29-35. doi:10.1097/YIC.0000000000000291