The listings of research below represents a compilation of scientific articles found on the topic, with a very brief overview description of each article/study. This compilation of research articles does not necessarily imply that there are adequate results to demonstrate safe and/or effective human use of any herb listed.
In a study of 100 women going thru labor, inhaling geranium aroma reduced anxiety and diastolic blood pressure. From: Fakari, F. R., Tabatabaeichehr, M., Kamali, H., Fakari, F. R., & Naseri, M. (2015). Effect of inhalation of aroma of geranium essence on anxiety and physiological parameters during first stage of labor in nulliparous women: a randomized clinical trial. Journal of caring sciences, 4(2), 135.
In low doses, bornyl acetate had a calming effect when inhaled by people. From: Matsubara, E., Fukagawa, M., Okamoto, T., Ohnuki, K., Shimizu, K., & Kondo, R. (2011). (-)-Bornyl acetate induces autonomic relaxation and reduces arousal level after visual display terminal work without any influences of task performance in low-dose condition. Biomedical Research, 32(2), 151-157.
Memory and calmness was increased while alertness was reduced in this randomized, placebo-controlled, double-blind, balanced-crossover study investigated tof the effect of extract of M. officinalis on 20 participants. From: Kennedy, D. O., Scholey, A. B., Tildesley, N. T. J., Perry, E. K., & Wesnes, K. A. (2002). Modulation of mood and cognitive performance following acute administration of Melissa officinalis (lemon balm). Pharmacology Biochemistry and Behavior, 72(4), 953-964.
Fragrance inhalation affected the sympathetic nervous system. Pepper, estragon oil, fennel, and grapefruit increased sympathetic activity, and rose and patchouli oils decreased sympathetic activity. Inhaling pepper oil increased plasma adrenaline levels while rose oil decreased adrenealine. From: Haze, S., Sakai, K., & Gozu, Y. (2002). Effects of fragrance inhalation on sympathetic activity in normal adults. The Japanese journal of pharmacology, 90(3), 247-253.
In this double blind, randomized trial of 34 females with incontinence, the inhalation of clary sage significantly reduced systolic blood pressure, diastolic blood pressure, and respiratory rate and lowered stress during a urodynamic examination. From: Seol, G. H., Lee, Y. H., Kang, P., You, J. H., Park, M., & Min, S. S. (2013). Randomized controlled trial for Salvia sclarea or Lavandula angustifolia: differential effects on blood pressure in female patients with urinary incontinence undergoing urodynamic examination. The Journal of Alternative and Complementary Medicine, 19(7), 664-670.
An aroma 4:2:1 blend of lavender, ylang ylang, and neroli reduced blood pressure and stress measurements in patients who were going to receive an angiography procedure. From: Song, E. J., & Lee, M. Y. (2018). Effects of Aromatherapy on Stress Responses, Autonomic Nervous System Activity and Blood Pressure in the Patients Undergoing Coronary Angiography: A Non-Randomized Controlled Trial. Journal of Korean Academy of Nursing, 48(1), 1-11.
In this clinical trial of 98 chronically stressed people, an extract of ashwagandha root and leaf extract resulted in reduced cortosol levels, pulse rate, and blood pressure over 30 and 60 days. Bio-actives in the plant include withanolide glycosides and aglycodes. From: Abedon, B., & Ghosal, S. (2008). A standardized Withania somnifera extract significantly reduces stress-related parameters in chronically stressed humans: a double-blind, randomized, placebo-controlled study.
There was a sedative effect in mice from lavender and linalool. From: Buchbauer, G., Jirovetz, L., & Jäger, W. (1991). Aromatherapy: evidence for sedative effects of the essential oil of lavender after inhalation. Zeitschrift für Naturforschung C, 46(11-12), 1067-1072.
In a stress test with 54 volunteers, kava and valerian reduced physiological reactivity. From: Cropley, M., Cave, Z., Ellis, J., & Middleton, R. W. (2002). Effect of kava and valerian on human physiological and psychological responses to mental stress assessed under laboratory conditions. Phytotherapy Research, 16(1), 23-27.
Linalool had a sedative effects on the Central Nervous System, including hypnotic, anticonvulsant and hypothermic properties, due to an inhibitory effect on glutamate binding in the (rat) cortex. From: Elisabetsky, E., Marschner, J., & Souza, D. O. (1995). Effects of linalool on glutamatergic system in the rat cerebral cortex. Neurochemical research, 20(4), 461-465.
In mice, Coriandrum sativum seed had an anxiolytic effect and may have sedative and muscle relaxant possibility. From: Emamghoreishi, M., Khasaki, M., & Aazam, M. F. (2005). Coriandrum sativum: evaluation of its anxiolytic effect in the elevated plus-maze. Journal of Ethnopharmacology, 96(3), 365-370.
Citrus aurantium (bergamot) reduced anxiety and was a sedative in mice. From: Carvalho-Freitas, M. I. R., & Costa, M. (2002). Anxiolytic and sedative effects of extracts and essential oil from Citrus aurantium L. Biological and Pharmaceutical Bulletin, 25(12), 1629-1633.
Neroli oil, citronellal and phenylethyl acetate showed a sedative effect in mice. From: Jäger, W., Buchbauer, G., Jirovetz, L., Dietrich, H., & Plank, C. (1992). Evidence of the sedative effect of neroli oil, citronellal and phenylethyl acetate on mice. Journal of Essential Oil Research, 4(4), 387-394.
Inhalation of an essential oil blended with lavender, ylang-ylang, marjoram, and neroli had a relaxing effect and reduced blood pressure in humans. From: Kim, I. H., Kim, C., Seong, K., Hur, M. H., Lim, H. M., & Lee, M. S. (2012). Essential oil inhalation on blood pressure and salivary cortisol levels in prehypertensive and hypertensive subjects. Evidence-Based Complementary and Alternative Medicine, 2012.
Inhalation of lavender and hyssop oil decreased mobility in mice that were treated with caffeine. Inhalation of ginger, thyme, peppermint, and cypress oil increased mobility. From: Lim, W. C., Seo, J. M., Lee, C. I., Pyo, H. B., & Lee, B. C. (2005). Stimulative and sedative effects of essential oils upon inhalation in mice. Archives of pharmacal research, 28(7), 770-774.
Peppermint enhanced memory whereas ylang-ylang impaired it, and peppermint increased alertness while ylang-ylang decreased it, but significantly increased calmness. From: Moss, M., Hewitt, S., Moss, L., & Wesnes, K. (2008). Modulation of cognitive performance and mood by aromas of peppermint and ylang-ylang. International Journal of Neuroscience, 118(1), 59-77.
Essential oil compounds that have a sedative effect were discussed. From: Buchbauer, G., Jirovetz, L., Jáger, W., Plank, C., & Dietrich, H. (1993). Fragrance compounds and essential oils with sedative effects upon inhalation. Journal of Pharmaceutical Sciences, 82(6), 660-664.
Inhalation of rose oil had a relaxing effect. From: Hongratanaworakit, T. (2009). Relaxing effect of rose oil on humans. Nat Prod Commun, 4(2), 291-6.
Application of ylang ylang on the skin caused relaxation in humans. From: Hongratanaworakit, T., & Buchbauer, G. (2006). Relaxing effect of ylang ylang oil on humans after transdermal absorption. Phytotherapy Research, 20(9), 758-763. Angelica essential oil exhibited anxiolytic effects similar to diazepam. From: Chen, S. W., Min, L., Li, W. J., Kong, W. X., Li, J. F., & Zhang, Y. J. (2004). The effects of angelica essential oil in three murine tests of anxiety. Pharmacology Biochemistry and Behavior, 79(2), 377-382.
Cedrol inhalation, as found in cedarwood, had a relaxant effect in humans, increasing parasympathetic activity and reducing sympathetic activity. From: Dayawansa, S., Umeno, K., Takakura, H., Hori, E., Tabuchi, E., Nagashima, Y., … & Nishijo, H. (2003). Autonomic responses during inhalation of natural fragrance of “Cedrol” in humans. Autonomic Neuroscience, 108(1), 79-86.
Cedrol inhalation had a sedative effects in multiple animal species. From: Kagawa, D., Jokura, H., Ochiai, R., Tokimitsu, I., & Tsubone, H. (2003). The sedative effects and mechanism of action of cedrol inhalation with behavioral pharmacological evaluation. Planta medica, 69(07), 637-641.
Inhalation of essential oil of valerian root and its constituents borneol, isoborneol, bornyl acetate, and isobornyl acetate caused a sedative effect in mice. From: Buchbauer, G., Jäger, W., Jirovetz, L., Meyer, F., & Dietrich, H. (1992). Effects of valerian root oil, borneol, isoborneol, bornyl acetate and isobornyl acetate on the motility of laboratory animals (mice) after inhalation. Die Pharmazie, 47(8), 620.
Valerenic acid from valerian root had a sedative effect in mice. From: Hendriks, H., Bos, R., Woerdenbag, H. J., & Koster, A. S. (1985). Central nervous depressant activity of valerenic acid in the mouse. Planta medica, 51(01), 28-31.
Roman chamomile essential oil showed a sedative, anti-inflammatory effect in rats. From: Rossi, T., Melegari, M., Bianchi, A., Albasini, A., & Vampa, G. (1988). Sedative, anti-inflammatory and anti-diuretic effects induced in rats by essential oils of varieties of Anthemis nobilis: a comparative study. Pharmacological research communications, 20, 71-74.
Fifty patients with hypertension were treated for 28 days with motherwort oil extract to show improved psycho-emotional status and arterial blood pressure. From: Shikov, A. N., Pozharitskaya, O. N., Makarov, V. G., Demchenko, D. V., & Shikh, E. V. (2011). Effect of Leonurus cardiaca oil extract in patients with arterial hypertension accompanied by anxiety and sleep disorders. Phytotherapy Research, 25(4), 540-543.
In a placebo controlled study, gotu kola has anxiolytic activity in humans related to measurements of acoustic startle response. From: Bradwejn, J., Zhou, Y., Koszycki, D., & Shlik, J. (2000). A double-blind, placebo-controlled study on the effects of Gotu Kola (Centella asiatica) on acoustic startle response in healthy subjects. Journal of clinical psychopharmacology, 20(6), 680-684.
California poppy had a nontoxic and sedative effect in mice. From: Rolland, A., Fleurentin, J., Lanhers, M. C., Younos, C., Misslin, R., Mortier, F., & Pelt, J. M. (1991). Behavioural effects of the American traditional plant Eschscholzia californica: sedative and anxiolytic properties. Planta medica, 57(03), 212-216.
Oral intake of a lozenge containing lavender oil, hop extracts, lemon balm and oat had a calming effect. From: Dimpfel, W., Pischel, I., & Lehnfeld, R. (2004). Effects of lozenge containing lavender oil, extracts from hops, lemon balm and oat on electrical brain activity of volunteers. European journal of medical research, 9(9), 423-431.
Catnip may have a sedative effect on humans. From: Osterhoudt, K. C., Lee, S. K., Callahan, J. M., & Henretig, F. M. (1997). Catnip and the alteration of human consciousness. Veterinary and human toxicology, 39(6), 373-375.
Catnip had a CNS depressing effect when fed to mice. From: Massoco, C. O., Silva, M. R., Gorniak, S. L., Spinosa, M. S., & Bernardi, M. M. (1995). Behavioral effects of acute and long-term administration of catnip (Nepeta cataria) in mice. Veterinary and human toxicology, 37(6), 530-533.
Inhalation of patchouli and its diacetone alcohol had a sedative effect in vivo. From: Ito, K., Akahoshi, Y., Ito, M., & Kaneko, S. (2016). Sedative effects of inhaled essential oil components of traditional fragrance Pogostemon cablin leaves and their structure–activity relationships. Journal of traditional and complementary medicine, 6(2), 140-145.