Valerian
In short
Summary of findings for quick reference
Valerian root is one of the deepest documented calming herbs in the European tradition. The written record runs without long gaps from Dioscorides, who described the root as phu in the first century, through the Renaissance herbals and the early pharmacopoeias, into the household Baldriantee of the German speaking and Alpine regions. Eleven traditions converge on the same use, mild nervous tension and restful sleep, which is why this entry sits at the highest historical significance tier.
The clinical picture is more cautious than the long tradition. The most careful assessment, the 2015 Cochrane review by Leach and Page, found high heterogeneity between studies and mixed findings on sleep quality, with no clear consistent effect. Earlier reviews by Bent and colleagues in 2006 and Fernandez San Martin and colleagues in 2010 reported only a gentle signal. The honest reading is a traditionally established, generally well tolerated plant, not a proven sleep aid.
Where the two readings meet is the European regulator. The EMA HMPCEuropean Medicines Agency, Committee on Herbal Medicinal Products (HMPC) monograph for Valerianae radix, the root of Valeriana officinalis, covers traditional use for mild nervous tension and as a sleep aid, with well established use recognised for standardised root extracts. Trials typically used 400 to 900 milligrams of extract taken 30 to 60 minutes before bed, and continuous use is generally limited to about four weeks. Note that the European monograph is for Valeriana officinalis; Indian valerian (Valeriana wallichii) and Mexican valerian (Valeriana edulis) are different species.
Clinical evidence ↔ Historical significanceWe display two separate evidence categories: clinical evidence from modern trials and historical significance from documented healing tradition. Both are valuable, but they answer different questions.Read more
In every encyclopedia entry we evaluate two distinct categories of evidence. Clinical evidence as used in trials meets a narrower but scientifically essential bar. At the same time, the hundreds of thousands of plant species worldwide have only partially been captured and tested in modern studies.
Alongside the trial picture our researchers compile a comprehensive overview of where and since when a plant has been used across different traditions of natural medicine. When a plant has been used as a medicinal plant in many cultures across many generations, that historical significance deserves to be visible too.
Our position: a truly informative overview emerges only when both categories sit side by side. We communicate transparently what counts as what.
Overview
Valerian (Valeriana officinalis), also known as garden valerian, is one of the classic European medicinal plants. The dried root is the part used, prepared most often as a tea, tincture, or capsule. The European Medicines Agency Committee on Herbal Medicinal Products (EMA HMPCEuropean Medicines Agency, Committee on Herbal Medicinal Products (HMPC)) describes valerian root as traditionally used for the relief of mild nervous tension and to aid sleep.
The clinical evidence is honestly mixed. A 2015 Cochrane review by Leach and Page summarised the trials on sleep quality and found significant heterogeneity between studies and no clear, consistent effect. Earlier reviews by Bent et al. (2006) and Fernandez-San-Martin et al. (2010) reported small signals. Valerian is best framed as a traditionally used, generally well-tolerated plant with mixed modern evidence rather than as a proven sleep aid.
History
Valerian appears in European herbal writing from antiquity onward. Galen described the root as a calming remedy for the nerves, and the Renaissance herbals of Lonicerus (1557) and Tabernaemontanus (1588) document the root for restlessness and disturbed sleep, before the Pharmacopoeia Londinensis of 1618 made valerian an official drug. The root has held a steady place in the monastic and household pharmacies of central Europe ever since.
In Austria and the wider German-speaking region, valerian root is a classic Heilkraut, and Baldriantee a familiar household remedy for restless evenings. The EMA HMPCEuropean Medicines Agency, Committee on Herbal Medicinal Products (HMPC) lists Valeriana officinalis in its monograph for traditional use in mild nervous tension and as a sleep aid. The German Commission E has also given the root a positive monograph for restlessness and nervous sleep disturbances.
Mechanism
Several compound groups have been described in the valerian root. The most studied are valerenic acid and isovaleric acid, both reported in laboratory work as modulators of the GABA-A receptor. That is the same receptor family targeted by benzodiazepines, though valerian acts much more mildly and the two are not directly comparable in clinical effect. Valepotriates have also been discussed, but are less well studied.
How these laboratory findings translate to the felt experience of drinking valerian tea is not fully clear from the available data. The amount of active compounds in a cup is small compared with concentrated extracts. Part of the perceived effect probably belongs to the ritual itself, the warmth and the deliberate evening pause, not only to the chemistry of the plant.
Clinical research on valerian includes several reviews. Bent et al. published a 2006 meta-analysis on sleep quality and reported a cautious signal toward subjectively better sleep. Fernandez-San-Martin et al. drew a similar conclusion in 2010. The most methodologically careful assessment comes from the 2015 Cochrane review by Leach and Page, which found high heterogeneity across studies and mixed findings on sleep quality, with no clear, consistent effect identifiable from the pooled data.
Most trials used standardised root extracts in the range of 400 to 900 milligrams, taken 30 to 60 minutes before bed. Tolerability and the side-effect profile were generally good across studies. Taken together, the research positions valerian as a traditionally established, well-tolerated plant with mixed evidence on efficacy, not as a proven sleep aid.
Usage
Forms and preparation
For tea, place about two to three grams of dried valerian root in a cup and pour over freshly boiled water. Cover the cup and let it steep for ten to fifteen minutes, then strain. A word of warning: the smell of valerian root is distinctive and often described as unpleasant. This is normal and not a sign of poor quality. Tincture doses commonly sit in the one to three millilitre range, taken in a little water. Capsules and tablets are taken according to package instructions. In all forms, valerian is more typically used over a stretch of days or weeks rather than as a single-evening intervention.
Dosage
In clinical trials, the typical dose has been a standardised root extract in the range of 400 to 900 milligrams, taken 30 to 60 minutes before bed. As a tea, two to three grams of root per cup is the customary range, with one or two cups in the evening. Tincture doses commonly sit between one and three millilitres per serving. Build slowly. Start at the lower end of the range and observe across several evenings before adjusting. The EMA HMPC recommends limiting continuous use to a maximum of four weeks. If complaints persist longer than that, consult a healthcare professional.
Safety
Look-alikes
Toxic look-alikes
Indian Valerian (Valeriana jatamansi)
A different species in the same genus, traditional in Ayurveda. Botanically related but not a direct substitute for Valeriana officinalis. Different active-compound profile.
Mexican Valerian (Valeriana edulis)
Used in traditional Central American practice and in some TCM-adjacent contexts. Different alkaloid and compound profile; not interchangeable one to one with Valeriana officinalis.
FAQs
How quickly does valerian act?
As a tea or tincture, a subjectively perceptible calming effect usually sets in about 30 to 60 minutes after intake. For standardised capsule extracts, many people report that the effect becomes more noticeable after several days of regular use. Valerian is more a plant for routine use than for an isolated acute situation.
Can valerian be combined with alcohol?
No. Alcohol and valerian amplify each other on the sedative axis. This combination should be avoided. The same applies to taking valerian alongside sedatives or sleep medications.
Does valerian really smell that strong?
Yes, the dried root has a very distinctive, often unpleasantly described smell. This is a normal feature of the plant and not a sign of poor quality. The aroma is more present in the tea than in the taste itself. Capsules and tablets largely sidestep the smell.
How long can I take valerian?
The EMA HMPC recommends limiting continuous use to a maximum of four weeks. If the complaints persist beyond that, consult a healthcare professional rather than simply extending use on your own.
Is valerian suitable for children?
For children under twelve, the EMA HMPC does not recommend valerian without medical advice. For older children, a clinician should decide whether and in what form valerian is appropriate.
Legal notice: The depiction of historical significance and traditional use is context within our encyclopedia and not a health claim for any product, not a treatment promise, and not a substitute for medical advice. What may be stated on product labels, product pages, or in advertising is governed by the applicable legal requirements.