Short answer
Valerian root (Valeriana officinalis) is one of the most studied herbal sleep aids. Meta-analyses suggest it may modestly improve how well people say they sleep, but the trials are inconsistent: some show benefit and some show none, and the best-quality evidence is mixed. It is generally well tolerated in studies, and it is not a substitute for treating chronic insomnia. [1] [2] [3] [4]
Key takeaways
- A 2006 meta-analysis of 16 randomized trials (1,093 people) found people on valerian were about 1.8 times as likely to report improved sleep, but most studies had method problems and there was publication bias. [1]
- A 2020 meta-analysis of 60 studies (6,894 people) found benefit for subjective sleep quality and anxiety, noting that inconsistent results may reflect the quality of extracts and that the whole root may work more reliably. [2]
- Not every trial is positive: two well-run studies, one in 227 cancer patients and one in older women with insomnia, found no improvement in sleep scores. [4] [3]
- There are also trials on menopausal sleep, hot flashes and period pain. Results are encouraging, small and from limited settings. [5] [6] [7]
- It causes drowsiness in some people, so avoid driving after a dose and avoid combining it with alcohol or sedatives.
Valerian is the herb most people reach for when they cannot sleep. It is also a good example of why a plant's reputation and its evidence do not always match.
The honest story is mixed. Some studies show clear benefit and others show none, and the difference may come down to the product. We will walk through both.
What is valerian root?
Valerian (Valeriana officinalis) is a perennial herb with pink-white flowers, native to Europe and Asia and widely grown across temperate regions. The part used is the root and rhizome, which has a strong, earthy, somewhat pungent smell when dried. It has a long history in European herbal medicine as a calming, sleep-promoting herb and is now sold worldwide as a sleep supplement.
How it might work is still being worked out. Researchers attribute the sedative and anxiety-reducing effects mainly to modulation of GABA, the brain's main calming chemical messenger, and a 2017 randomized study in humans found a valerian root extract changed cortical excitability in a way consistent with that. [8] No single compound has been confirmed as the active one, which is partly why different products behave differently.
What research says about valerian for sleep
The big meta-analyses
A 2006 systematic review and meta-analysis pooled 16 randomized, placebo-controlled trials with 1,093 patients. Six studies reported a yes-or-no result for improved sleep, and those showed a relative risk of improved sleep of 1.8 (95% CI 1.2 to 2.9). The authors cautioned that most studies had significant methodologic problems, doses and preparations varied widely, and there was evidence of publication bias. Their conclusion: valerian might improve sleep quality without producing side effects, and better studies were needed. [1]
A 2020 systematic review and meta-analysis included 60 studies with 6,894 participants and ran meta-analyses on subjective sleep quality (10 studies, 1,065 people) and anxiety (8 studies, 535 people). It concluded valerian could be a safe and effective herb to promote sleep and prevent associated disorders. It also offered an explanation for the inconsistent trial results: variable quality of herbal extracts, with more reliable effects possible from the whole root or rhizome, and better outcomes when combined with suitable herbal partners. It recorded no severe adverse events in people aged 7 to 80. [2]
A 2003 family-physician review concluded that valerian improves subjective sleep when taken nightly over one to two weeks and appears safe for mild to moderate insomnia, that the evidence for a single dose is contradictory, that data for anxiety are limited, and that long-term safety studies are lacking. [9]
Trials that did not find a benefit
The trials that failed matter too. A phase III study of 227 people undergoing cancer treatment gave 450 mg of valerian or placebo an hour before bed for eight weeks. On the primary measure of sleep quality, the two groups were virtually identical (scores of 51.4 and 49.7, p = 0.70). Exploratory results suggested less fatigue and less drowsiness on valerian, and side effects were no different from placebo. [4] A smaller crossover trial in 16 older women with insomnia tested 300 mg of concentrated extract nightly for two weeks and found no improvement on any sleep measure, including lab-recorded sleep. [3]
A positive standardized-extract trial
A 2024 randomized, double-blind trial gave 80 adults with sleep complaints a standardized valerian extract or placebo for eight weeks. In the 72 who finished, sleep quality scores improved significantly versus placebo from day 14 on, time to fall asleep fell and sleep efficiency rose on wrist actigraphy, and anxiety and daytime drowsiness scores dropped. [10] It was an industry-style standardized extract, not a cup of root tea.
Menopause: sleep and hot flashes
In a triple-blind trial of 100 postmenopausal women with insomnia, 530 mg of concentrated valerian extract twice daily for four weeks improved sleep quality compared with placebo (30% versus 4% improved, p < 0.001). [5] In a separate triple-blind trial of 60 postmenopausal women, the same dose for two months reduced hot flash severity at one and two months and frequency at two months. [6] Both are single-country trials of capsule extracts, and neither tested a tea.
Period pain (dysmenorrhea)
A 2025 meta-analysis of five controlled trials (201 treated and 207 control participants) found valerian reduced primary dysmenorrhea pain by about 1.03 points on a 0 to 10 scale versus control. Heterogeneity between trials was very high (I² = 90%), and the authors called for standardized larger trials. [7]
| Use | Evidence level | What we know |
|---|---|---|
| Better subjective sleep | Meta-analyses of RCTs, mixed | Pooled benefit in subjective sleep, but inconsistent trials and bias concerns. [1] [2] |
| Objective sleep (lab-measured) | Small trial, no benefit | No improvement in 16 older women with insomnia. [3] |
| Sleep in cancer treatment | Phase III RCT, no primary benefit | No difference on the primary sleep score. [4] |
| Anxiety | Meta-analysis (8 studies) | Pooled benefit reported; limited data per the 2003 review. [2] [9] |
| Menopausal sleep and hot flashes | Two small RCTs | Improved sleep and hot flashes vs placebo. [5] [6] |
| Period pain | Meta-analysis (5 trials) | Pain reduction, high heterogeneity. [7] |
Valerian root side effects and safety
Across the trials above, side effects were generally minor and often no different from placebo. [4] [3] The 2020 meta-analysis found no severe adverse events across studies. [2] But valerian is a sedating herb, and a few specific cautions belong in any honest guide.
- Drowsiness: do not drive or operate machinery after taking it until you know how it affects you, and avoid alcohol and other sedatives with it.
- Liver: there is at least one case report of valerian-associated hepatitis that responded to steroids. It is rare, but anyone with liver disease should ask a clinician. [11]
- Overdose and withdrawal: one case report describes an overdose of about 20 times the recommended dose that resolved within 24 hours with mild symptoms, [12] and another case report describes delirium after withdrawal from valerian root, a reason not to treat it as an open-ended nightly habit without medical advice. [13]
- Pregnancy and breastfeeding: there is not enough safety data. Avoid it.
- Surgery: tell your anesthesiologist, since sedating herbs can matter around procedures. [14]
How to take valerian root
Our label directions for the cut root: bring 2 cups of water to a boil, add 1 heaping tablespoon of valerian, reduce to low, cover and simmer for 30 minutes. Strain and drink warm, one hour before or after meals, ideally before bed. The aroma is strong and earthy, and many people add mint or a little honey to the cup.
On dose: the trials used capsules of concentrated extract at 300 to 530 mg, taken at bedtime in two studies and twice a day in another, for two to eight weeks. [3] [4] [5] A home decoction of root is a different, unmeasured preparation, so we cannot say a cup equals a capsule. Start with a small cup and see how you feel the next morning.
How to buy valerian well
The 2020 meta-analysis suggests quality varies and that whole root may be more reliable than some extracts. [2] Look for Valeriana officinalis named on the label, whole or cut root rather than anonymous powder, and a freshness date, because some of the active constituents are described as relatively unstable. Ours is wild-harvested root from the Ecuadorian Andes. View Valerian. It is also in our Scales of Balance blend.
Frequently asked questions
Does valerian root work for sleep?
How long does valerian take to work?
Studies mostly look at nightly use for one to eight weeks. A 2003 review concluded benefit shows up with nightly use over one to two weeks and that single-dose evidence is contradictory. [9]
What are the side effects of valerian root?
Can valerian help with anxiety?
How do you make valerian root tea?
Simmer rather than steep: 2 cups of water to a boil, 1 heaping tablespoon of root, reduce to low, cover, simmer 30 minutes, strain and drink warm before bed.
Is it safe to take valerian every night?
Does valerian help with hot flashes or period pain?
Where can I buy valerian root in the USA?
Look for Valeriana officinalis root with the botanical name and a freshness date. Kawsaypac sells wild-harvested valerian root from the Ecuadorian Andes, shipped across the USA: view Valerian.
References
- Bent S, Padula A, Moore D, et al. (2006). Valerian for sleep: a systematic review and meta-analysis. Am J Med. PubMed 17145239 · DOI
- Shinjyo N, Waddell G, Green J (2020). Valerian Root in Treating Sleep Problems and Associated Disorders-A Systematic Review and Meta-Analysis. J Evid Based Integr Med. PubMed 33086877 · DOI
- Taibi DM, Vitiello MV, Barsness S, et al. (2009). A randomized clinical trial of valerian fails to improve self-reported, polysomnographic, and actigraphic sleep in older women with insomnia. Sleep Med. PubMed 18482867 · DOI
- Barton DL, Atherton PJ, Bauer BA, et al. (2011). The use of Valeriana officinalis (Valerian) in improving sleep in patients who are undergoing treatment for cancer: a phase III randomized, placebo-controlled, double-blind study (NCCTG Trial, N01C5). J Support Oncol. PubMed 21399726 · DOI
- Taavoni S, Ekbatani N, Kashaniyan M, et al. (2011). Effect of valerian on sleep quality in postmenopausal women: a randomized placebo-controlled clinical trial. Menopause. PubMed 21775910 · DOI
- Jenabi E, Shobeiri F, Hazavehei SMM, et al. (2018). The effect of Valerian on the severity and frequency of hot flashes: A triple-blind randomized clinical trial. Women Health. PubMed 28278010 · DOI
- Rabiei F, Delavar MA, Mirabi P, et al. (2025). Effect of Valeriana officinalis on Primary Dysmenorrhea: A Systematic Review and Meta-Analysis. Rev Recent Clin Trials. PubMed 40965071 · DOI
- Mineo L, Concerto C, Patel D, et al. (2017). Valeriana officinalis Root Extract Modulates Cortical Excitatory Circuits in Humans. Neuropsychobiology. PubMed 29035887 · DOI
- Hadley S, Petry JJ (2003). Valerian. Am Fam Physician. PubMed 12725454
- Chandra Shekhar H, Joshua L, Thomas JV (2024). Standardized Extract of Valeriana officinalis Improves Overall Sleep Quality in Human Subjects with Sleep Complaints: A Randomized, Double-Blind, Placebo-Controlled, Clinical Study. Adv Ther. PubMed 37899385 · DOI
- Kia YH, Alexander S, Dowling D, et al. (2016). A case of steroid-responsive valerian-associated hepatitis. Intern Med J. PubMed 26813905 · DOI
- Willey LB, Mady SP, Cobaugh DJ, et al. (1995). Valerian overdose: a case report. Vet Hum Toxicol. PubMed 8540231
- Burke H, Jiang S, Chatham P, et al. (2020). Delirium After Withdrawal From Valerian Root: A Case Report. Psychosomatics. PubMed 32576405 · DOI
- Kleinschmidt S, Rump G, Kotter J (2007). [Herbal medications. Possible importance for anaesthesia and intensive care medicine]. Anaesthesist. PubMed 17898965 · DOI