Review Article

Plant Extracts for Sleep Disturbances: A Systematic Review

Table 1

List of studies with selected compounds.

CompoundFirst authors (year published)DesignTotal patientsInterventionReported outcomes/resultsJournalJadad scale

ValerianTaavoni 2013 [30]Triple-blind,
Randomized placebo-controlled trial
100160 mg of essence of valerian and lemon balmImprovement in sleep quality (PSQI)Complementary Therapies in Clinical Practice3
Taavoni 2011 [29]Triple-blind,
Randomized placebo-controlled trial
100530 mg valerian extractImprovement in sleep quality (PSQI)Menopause3
Barton 2011 [35]Double-blind
Randomized placebo-controlled trial
119450 mg of valerianNo improvement in sleep quality (PSQI)The Journal of Supportive Oncology3
Cuellar 2009 [34]Triple-blind,
Randomized placebo-controlled trial
37800 mg of valerianNo improvement in sleep quality (PSQI)Alternative Therapies in Health and Medicine5
Waldschütz 2008 [37]Open-label, prospective cohort study409Doses were at physicians’ judgmentsImproved sleep latency and durationThe Scientific World Journal1
Oxman 2007 [33]Web-based randomized placebo-controlled trial405200 mg extract per tablet (valerina forte).No improvement in sleep quality perceivedPLoS One5
Müller 2006 [31]Open, multicentre study918Euvegals forte (160 mg valerian root)Reduced dyssomniaPhytomedicine1
Jacobs 2005 [39]Internet-based randomized, placebo-controlled trial3912 valerian softgel capsules (3.2 mg of valerenic acids)No changes in ISIMedicine5
Diaper 2004 [40]Placebo-controlled three way crossover16Acute valerian 300 mg or valerian 600 mgNo changes in EEG parameters or psychometric measuresPhytotherapy Research5
Coxeter 2003 [41]Randomized n-of-1 trials24225 mg V. officinalis root and rhizome extractNo changes in total sleep time or number of night awakeningsComplementary Therapies in Medicine5
Ziegler 2002 [28]Randomized, double-blind, comparative trial202600 mg/die valerian extractImprovement in sleep qualityEuropean Journal of Medical ResearchNA
Poyares 2002 [27]Double-blind,
Randomized placebo-controlled trial
37100 mg valerian (valmane)Improvement in sleep quality and wake time after sleep onsetProgress in Neuropsychopharmacology and Biological Psychiatry3
Herrera-Arellano 2001 [26]Double-blind, cross-over, placebo-controlled study20450 mg of valerianImprovement in sleep quality and morning sleepinessPlanta Medica3
Wheatley 2001 [38]Cross-over study compared to kava19600 mg of valerianImprovement in insomnia severity scoresPhytotherapy Research1
Donath 2000 [36]Double-blind, cross-over, placebo-controlled study16300 mg dry extract valerian (sedonium)Improvement in slow-wave sleep latencyPharmacopsychiatry4
Lindahl 1988 [32]Double-blind,
Randomized placebo-controlled trial
27400 mg of valepotriatesImprovement in sleep qualityPharmacology Biochemistry and Behavior4
Leathwood 1982 [25]Double-blind,
Randomized placebo-controlled trial
128400 mg valerian for 3 daysImprovement in sleep quality and wake time after sleep onsetPharmacology Biochemistry and Behavior4
LavenderKasper 2015 [45]Double-blind,
Randomized placebo-controlled trial
17080 mg of silexan daily for 10 weeksImprovement in sleep quality (PSQI) and anxiety (HAMA)European Neuropsychopharmacology4
Uehleke 2012 [46]Open-label, exploratory trial471 × 80 mg/day silexan over 6 weeksReduced waking-up frequency and durationPhytomedicine1
Kasper 2010 [44]Double-blind,
Randomized placebo-controlled trial
22180 mg of silexan daily for 10 weeksImprovement in sleep quality (PSQI) and anxiety (HAMA)International Clinical Psychopharmacology5
Woelk 2010 [43]Double-blind,
Randomized lorazepam-controlled trial
771 × 80 mg/day silexan over 6 weeksImprovement in anxiety (HAMA) and sleep quality (sleep diary)Phytomedicine4
HopScholey 2017 [47]Double-blind,
Randomized placebo-controlled trial
171LZComplex3 (lactium, Zizyphus, Humulus lupulus, magnesium, and vitamin B6) hop 500 mg for 2 weeksNo changes in sleep quality (PSQI)Nutrients5
Cornu 2010 [48]Double-blind,
Randomized placebo-controlled trial
101Two gelatine capsules of Cyclamax® (50 mg hop, 260 mg soya oil, 173 mg Cannabis sativa) per day for a monthNo effects on sleep quality (LSEQ), melatonin metabolism, and sleep-wake cycleBMC Complementary and Alternative Medicine3

ChamomileAdib-Hajbaghery 2017 [49]Single-blind randomized controlled trial60200 mg twice a day for 28 daysImprovement in general sleep quality and sleep latency (PSQI)Complementary Therapies in Medicine3
Chang 2016 [50]A single-blinded, randomized controlled80one cup of chamomile tea per day for 2 weeksImprovement in PSQSJournal of Advanced Nursing3
Zick 2011 [51]Double-blind, randomized, placebo-controlled pilot trial34270 mg of chamomile twice daily for 28 daysNo significant improvement in ISI and PSQIBMC Complementary and Alternative Medicine5

HawthornHanus 2003 [52]Double-blind, randomized, placebo-controlled trial264150 mg twice daily for 3 monthsReduction in Hamilton Anxiety ScaleCurrent Medical Research and Opinion4

St. John’s wortAl-Akoum 2009 [53]Pilot double-blind, randomized47900 mg three times dailyImprovement in general sleep quality (SPS)Menopause5

RosemaryNematolahi 2018 [54]Double-blinded randomized placebo-controlled trial68500 mg rosemaryImprovement in sleep quality (PSQI)Complementary Therapies in Clinical Practice3
Valerian + hopMaroo 2013 [56]Double-blinded randomized Zolpidem-controlled trial78300 mg valerian, 80 mg passion flower, and 30 mg hopImprovement in total sleep time, sleep latency, number of nightly awakenings, and ISIIndian Journal of Pharmacology5
Dimpfel 2008 [55]Double-blinded randomized placebo-controlled trial42460 mg of valerian and 460 mg of hop single doseImprovement in sleep quality (deep sleep) and sleep quantityEuropean Journal of Medical Research3
Koetter 2007 [57]Double-blinded randomized placebo-controlled trial27500 mg of valerian and 120 mg of hop for 4 weeksImprovement in sleep latencyPhytotherapy Research2
Morin 2005 [58]Double-blinded randomized placebo-controlled trial1842 tablets of 187 mg of valerian and 41.9 mg of hop for 28 daysImprovement in quality of life (physical component)Sleep3
Sun 2003 [59]Open, noncomparative trial72200 mg valerian, 100 mg hop, kava and other componentsImprovement in sleep quality, sleep latency, sleep duration, sleep disturbance (PSQI)The Journal of Alternative and Complementary Medicine0

SPS = sleep problem scale, PSQI = Pittsburg sleep quality inventory, PSQS = postpartum sleep quality scale, LSEQ = Leeds sleep evaluation questionnaire, and ISI = insomnia severity index.