Valerian

What is valerian (kediotu), and which parts are used?

According to NCCIH, valerian is a plant native to Europe and Asia that also grows in North America; it has been used for medicinal purposes since ancient Greek and Roman times and has historically been used for insomnia, migraine, fatigue, and stomach cramps. Today it is marketed for insomnia, anxiety, stress, and depression; the root and rhizome (underground stem) are used medicinally. ^[1] The plant known in Turkish as “kediotu” is named “Valerian, kediotu” in the Ministry of Agriculture and Forestry Plant List, and the part used is the root. ^[8]

Studies have used whole root/rhizome, extracts, and mixtures with other herbs; Shinjyo and colleagues suggest the variable quality of plant extracts as a possible reason for the inconsistency of clinical study results and state that more reliable effects can be expected from whole root/rhizome; this is the review’s interpretation, not a directly comparative result. ^[3]

Role in the body and purpose of use

Valerian is not a nutrient; it has no required function or deficiency in the body. NCCIH states that a sleep-inducing effect of valerian is possible but has not been proven. ^[1] In their introduction, Valente and colleagues state that valerian is one of the most commonly used herbal agents for sleep disorders, particularly for difficulty falling asleep in young adults, and that it is also recommended by general practitioners and psychiatrists; this is introductory information on usage patterns, not a finding of the review. ^[4] In the sections below, sleep, anxiety, and other claims are given separately on the basis of controlled studies. There are also pages covering other options for sleep: melatonin and magnesium.

Does valerian help sleep?

The 2006 meta-analysis by Bent and colleagues included placebo-controlled RCTs of valerian for sleep quality: 16 studies, 1,093 patients in total. Most studies had important methodological problems; dose, preparation, and treatment duration varied widely. In the binary outcome (sleep improved/did not improve) reported by six studies, a statistically significant benefit was seen (relative risk of improvement 1.8; 95% CI 1.2–2.9), but there was evidence of publication bias for this summary measure. The study was NIH-supported. ^[2]

The 2020 review by Shinjyo and colleagues covered 60 studies (n = 6,894); meta-analyses were done on 10 studies (n = 1,065) for subjective sleep quality and 8 studies (n = 535) for anxiety. The authors concluded that valerian may be a safe and effective herb for supporting sleep; they also stated that extract quality and standardization methods need to be reviewed. ^[3]

The 2024 umbrella review by Valente and colleagues included only systematic reviews: of 70 records, 8 articles were eligible for qualitative analysis. The authors found the safety profile good but concluded that there was no evidence of efficacy for treating insomnia; they stated that although an improvement in subjective sleep quality appears, this was not shown with quantitative or objective measures, and that the existing studies are few, heterogeneous, and of low methodological quality. ^[4]

The systematic review by Leach and Page covered 14 RCTs with 1,602 participants with insomnia; four herbal monopreparations (valerian, chamomile, kava, and wuling) were identified. In none of the thirteen clinical efficacy measures was there a statistically significant difference between any herbal medicine and placebo or active control; the number of adverse events per person was higher with valerian than with placebo. ^[5]

Read side by side, these four results give the following picture: benefit was seen in subjective sleep quality in some meta-analyses; no evidence of efficacy was found for an insomnia diagnosis. These two statements do not conflict but answer different questions: improvement on a scale and treatment of an insomnia disorder are not the same outcome.

Why do the results differ from one another?

Three reviews give different answers to the same question, and each offers a different rationale. Bent and colleagues state that dose, preparation, and treatment duration varied widely and that most studies had important methodological problems. ^[2] Shinjyo and colleagues attribute the inconsistency to variability in extract quality; they also draw attention to the multiplicity of active components and the unstable nature of some, and say that quality control processes such as standardization and shelf life should be reviewed. ^[3] Valente and colleagues, by contrast, emphasize that studies are few, heterogeneous, and of low quality. ^[4] These explanations show that valerian is not “one product” but a set of different preparations.

What do insomnia guidelines say about valerian?

NCCIH reports that evidence is inconsistent for sleep problems and that the AASM’s 2017 clinical practice guideline made a recommendation against the use of valerian in chronic insomnia in adults. ^[1] The summary of the AASM guideline recommends that valerian not be used, compared with no treatment, for the treatment of sleep-onset or sleep-maintenance insomnia in adults (weak recommendation). The same guideline states that, according to GRADE, a weak recommendation should not be interpreted as an indicator of ineffectiveness and that it reflects lower certainty. ^[6] The guideline also gave the same type of (weak) “do not use” recommendation for trazodone, tiagabine, diphenhydramine, melatonin, and tryptophan; valerian is not the only substance in this group. ^[6]

Does valerian help anxiety?

The Cochrane review (Miyasaka et al., search August 4, 2006) could find only one RCT: 36 patients with generalized anxiety disorder, a 4-week pilot study; valerian, diazepam, and placebo were compared. There was no significant difference between valerian and placebo in the HAM-A total score; improvement was more marked in the diazepam group according to the STAI-Trait score. There was also no significant difference between valerian and diazepam in HAM-A scores; the number of patients reporting side effects and dropout rates also did not differ significantly among the three groups. The authors state that, because it is a single small study, it is not possible to reach a conclusion about efficacy and safety. ^[7] In later years, Shinjyo and colleagues conducted a meta-analysis of 8 studies (n = 535) for the outcome of reducing anxiety; the pooled effect size is shown in the article only in the forest plot, not as a number. ^[3] NCCIH, however, states that there is not enough evidence to reach a conclusion for anxiety, depression, premenstrual syndrome, dysmenorrhea (menstrual cramps), and stress. ^[1]

The single RCT in Cochrane was conducted in patients with diagnosed generalized anxiety disorder, whereas the meta-analysis by Shinjyo and colleagues pools 8 studies. Because the two results rest on different populations and different numbers of studies, they cannot be directly compared. ^{[7] [3]}

Is there evidence for menopausal symptoms?

NCCIH reports that three small studies suggest that valerian may be helpful for menopausal symptoms but that the evidence is not sufficient to say definitively. ^[1]

Is valerian safe, and are there drug interactions?

According to NCCIH, research suggests that valerian is generally safe in most adults for short-term use; it has been used at doses of 300–600 milligrams per day for up to 6 weeks without apparent safety problems, and long-term safety is unknown. Side effects include headache, stomach upset, mental dullness, restlessness, and vivid dreams; when stopped abruptly after chronic use, withdrawal symptoms such as anxiety, nervousness, heart-related discomfort, insomnia, and rarely hallucinations may occur. Liver damage has been reported in very rare cases, mostly when taken with other herbs; the long-term effect of valerian on liver function is unknown. ^[1]

Because a sleep-inducing effect is possible (but unproven), NCCIH states that valerian should not be taken together with alcohol or sedatives; little is known about its safety in pregnancy and breastfeeding. ^[1] Shinjyo and colleagues report that no serious adverse events associated with valerian intake were found in people aged 7–80 years; this is a report based on the studies included in the review, to be read together with the finding of Leach and Page of more adverse events per person. ^{[3] [5]}

Who needs additional precautions?

According to the points reported by NCCIH, situations requiring special attention are: use together with alcohol or sedative medicines; pregnancy and breastfeeding (little data); abrupt discontinuation after chronic use (withdrawal symptoms); and the unknown long-term effect on liver function. ^[1] For people taking regular medicines, NCCIH states that a health professional should be consulted before any herbal product.

What is the status of valerian in Türkiye?

In the July 16, 2026 update of the Ministry of Agriculture and Forestry Plant List, Valeriana officinalis (valerian, kediotu; root) is listed as positive (P). ^[8] In the September 21, 2026 version of the Restricted Substances List for Food Supplements, 24 mg/day is written in the ages 11 and over maximum column in the row “Valerenic acid (from Valeriana officinalis extract)” (published June 27, 2016); the ages 4–10 columns are empty. ^[9] This limit is the amount of a marker compound (valerenic acid); it is not in the same unit as the root or extract weight used in studies. The general framework for food supplements is given on the Supplement regulation in Türkiye page. This guide does not recommend products or places of purchase and does not set personal doses.

Evidence table: claim, population, and limits