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Laura Shane-McWhorter

, PharmD, University of Utah College of Pharmacy

Last full review/revision Jul 2020| Content last modified Jul 2020
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Valerian’s (Valeriana officinalis) root and rhizomes (underground stems) contain its active ingredients, including valepotriates and pungent odiferous oils.


Valerian is used as a sedative and sleep aid and is especially popular in Europe.

Some people take valerian for headaches, depression, irregular heartbeat, and trembling. It is usually used for short periods of time (eg, 2 to 6 weeks), at dosages of 400 to 600 mg of dried root once/day 1 hour before bedtime.


In a 2006 meta-analysis of 16 randomized, placebo-controlled trials of valerian, the evidence suggested that valerian might improve sleep quality and shorten the time needed to fall asleep without producing adverse effects (1). However, there are still insufficient clinical data to confirm whether valerian is effective for insomnia (2-3). A 2011 randomized controlled trial in 100 women found that compared to placebo valerian improved sleep quality in women experiencing insomnia during menopause (4). There is interest in using valerian to treat obsessive-compulsive disorder, and there is evidence of benefit per a pilot 8-week randomized controlled study (5). There is not enough scientific evidence to determine whether valerian works for headaches, depression, irregular heartbeat, and trembling.

Adverse effects

Studies suggest that it is generally safe to give valerian at the usual doses. Valerian is not recommended for women who are pregnant or breastfeeding. Possible sedation from valerian may affect driving or other activities requiring alertness.

Drug interactions

In vitro studies have suggested valerian to inhibit both CYP3A4 metabolism and p-glycoprotein activity (6), but no clinical studies have shown any drug metabolism interactions.

Valerian may prolong the effect of other sedatives (eg, barbiturates) and affect driving or other activities requiring alertness.

Valerian references

  • Bent S, Padula A, Moore D, et al: Valerian for sleep: a systematic review and meta-analysis. Am J Med 119(12):1005–1012, 2006. doi:  10.1016/j.amjmed.2006.02.026.

  • Fernández-San-Martín MI, Masa-Font R, Palacios-Soler L, et al: Effectiveness of valerian on insomnia: a meta-analysis of randomized placebo-controlled trials. Sleep Med11(6):505-511, 2010. doi: 10.1016/j.sleep.2009.12.009. 

  • Taibi D, Landis C, Petry H, et al: A systematic review of valerian as a sleep aid: safe but not effective. Sleep Med Rev 11(3):209–223, 2007. doi: 10.1016/j.smrv.2007.03.002.

  • Taavoni S, Ekbatani N, Kashaniyan M, et al: Effect of valerian on sleep quality in postmenopausal women: a randomized placebo-controlled clinical trial. Menopause 18(9):951-955, 2011. doi: 10.1097/gme.0b013e31820e9acf.

  • Pakseresht S, Boostani H, Sayyah M: Extract of valerian root (Valeriana officinalis L.) vs. placebo in treatment of obsessive-compulsive disorder: a randomized double-blind study. J Complement Integr Med 8, 2011. doi: 10.2202/1553-3840.1465.

  • Hellum BH, Nilsen OG: In vitro inhibition of CYP3A4 metabolism and P-glycoprotein-mediated transport by trade herbal products. Basic Clin Pharmacol Toxicol 102(5):466-475, 2008. doi: 10.1111/j.1742-7843.2008.00227.x. 

More Information

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