A double-blind, placebo-controlled investigation of the effects of Passiflora incarnata (passionflower) herbal tea on subjective sleep quality

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#adolescent #adult #australia #beverages #double-blind-method

A double-blind, placebo-controlled investigation of the effects of Passiflora incarnata (passionflower) herbal tea on subjective sleep quality

Ngan et al., 2011 | Phytother Res | Rct

Citation

Ngan A, Conduit R. A double-blind, placebo-controlled investigation of the effects of Passiflora incarnata (passionflower) herbal tea on subjective sleep quality. Phytother Res. 2011-Aug;25(8):1153-9. doi:10.1002/ptr.3400

Abstract

Passiflora incarnata is a traditional herbal sedative, anxiolytic and a popular sleep aid used for the treatment of sleep disturbance. Several controlled experiments have demonstrated enhanced sleep in laboratory animals, but clinical trials in humans are lacking. The aim of the present study was to investigate the efficacy of Passiflora incarnata herbal tea on human sleep, as measured using sleep diaries validated by polysomnography (PSG). This study featured a double-blind, placebo-controlled, repeated-measures design with a counterbalanced order of treatments (passionflower vs placebo tea), separated by a 1 week 'washout' period. Forty-one participants (18-35 years) were exposed to each treatment for a week, whereby they consumed a cup of the tea and filled out a sleep diary for 7 days, and completed Spielberger's state-trait anxiety inventory on the seventh morning. Ten participants also underwent overnight PSG on the last night of each treatment period. Of six sleep-diary measures analysed, sleep quality showed a significantly better rating for passionflower compared with placebo (t(40) = 2.70, p < 0.01). These initial findings suggest that the consumption of a low dose of Passiflora incarnata, in the form of tea, yields short-term subjective sleep benefits for healthy adults with mild fluctuations in sleep quality.

Key Findings

These initial findings suggest that the consumption of a low dose of Passiflora incarnata, in the form of tea, yields short-term subjective sleep benefits for healthy adults with mild fluctuations in sleep quality.

Outcomes Measured

  • sleep quality
  • anxiety

Population

Field Value
Population See abstract
Sample Size See abstract
Age Range 18-35 years
Condition sleep

MeSH Terms

  • Adolescent
  • Adult
  • Australia
  • Beverages
  • Double-Blind Method
  • Female
  • Humans
  • Male
  • Passiflora
  • Phytotherapy
  • Placebos
  • Plant Extracts
  • Polysomnography
  • Sleep
  • Young Adult

Evidence Classification

  • Level: Rct
  • Publication Types: Journal Article, Randomized Controlled Trial, Research Support, Non-U.S. Gov't
  • Vertical: passionflower

Provenance

Source extracted via PubMed E-utilities API on 2026-04-09