Capitate valerian

Other Names

clustered valerianmountain valeriansharp-leaved valeriansharpleaf valeriansubalpine valerianValeriana capitataValeriana capitata Pall. ex Linkvalériane capitée

Synopsis

Capitate Valerian (Valeriana capitata Pall. ex Link)

Identity and Botanical Classification

Accepted Scientific Name and Synonymy

Capitate valerian is the common English name for Valeriana capitata Pall. ex Link, a species first described by the German-Russian naturalist Peter Simon Pallas and formally published by Johann Heinrich Friedrich Link. The epithet capitata (Latin: "head-shaped") refers to the characteristically dense, rounded, capitate (head-like) flower cluster that distinguishes this species from many of its congeners. It is sometimes listed in older and regional references under the informal synonym Valeriana acutiloba var. capitata, and it has occasionally been treated as "mountain valerian" in Yukon and Canadian literature. Taxonomically recognized subspecies include Valeriana capitata subsp. capitata and Valeriana capitata subsp. gotvanskyi. The species belongs to the family Caprifoliaceae (formerly classified within the segregate family Valerianaceae, now subsumed into Caprifoliaceae following molecular phylogenetic revisions).

Morphology

Valeriana capitata is a herbaceous perennial plant with a long, creeping rhizome; it produces straight, stout stems around 15–30 cm tall, occasionally up to 65 cm. The plant is harvested from the wild for local use as a food, medicine, and source of materials. Capitate valerian is a 12–50 cm plant with dark green leaves and a dense flowering head. The single stem bears large ovate basal leaves and often 2–3 leaf nodes with 2–4 smaller, linear, pointed leaves higher on the stem. The plant is hermaphrodite, bearing both male and female organs, and is pollinated by insects. It is suitable for light (sandy), medium (loamy), and heavy (clay) soils, and for mildly acid, neutral, and basic (mildly alkaline) soils. It cannot grow in the shade and prefers moist or wet soil.

Natural Range and Habitat

Valeriana capitata is a very cold-tolerant plant, growing wild in the arctic zone and the alpine mountain belt. Its natural range encompasses Alaska, the Aleutian Islands, Altay, British Columbia, Buryatiya, Chita, Irkutsk, Kamchatka, Kazakhstan, Khabarovsk, Krasnoyarsk, Magadan, Mongolia, northern European Russia, the Northwest Territories, Tuva, West Siberia, Yakutiya, and the Yukon. It lives in moist soil or bogs in full sun to part shade, and is often found near streams in tundra or open woods. The species thus occupies a circumpolar boreal-to-arctic footprint spanning Russia, Central Asia, and subarctic North America.

Relationship to the Broader Valeriana Genus

The genus Valeriana comprises plants in the family Caprifoliaceae, including more than 200 species worldwide. It comprises approximately 250 species, and 11 out of the 28 Chinese varieties (including one variant) are used as herbal medicines. V. capitata is one of the less intensively studied members of the genus from a pharmacological standpoint; the great preponderance of published phytochemical and clinical research concerns V. officinalis L. (common or garden valerian) and several Asian relatives such as V. jatamansi Jones and V. amurensis. The roots of Valeriana acutiloba (capitata) are described as very similar to garden valerian (Valeriana officinalis). Because no peer-reviewed phytochemical studies have been published exclusively on isolated V. capitata material, the chemical and pharmacological profile of this species is understood primarily by analogy and by its documented botanical similarity to closely related species within the genus.

Traditional and Historical Use

Indigenous Peoples of the Circumpolar North

The cooked root of Valeriana capitata has been used historically as a powerful sedative and diuretic. The root is considered poisonous when uncooked. Documented edible parts include the seed, which is parched, and the root, which is steamed for 24 hours before consumption. The root has also been used as an incense. Specifically, the dried root has been used as an incense.

Ethnobotanically, indigenous people throughout the northern United States and Canada have used local valerian species in diverse ways, including as food, in charms, in herbalism for people and horses, as a smoked plant, for incense, and in ceremonies. In subarctic and arctic regions where V. capitata is the primary native valerian, these uses would have applied specifically to this species.

Traditional Preparations

The most consistently documented traditional preparation of V. capitata root involves prolonged cooking or steaming — a critical step given the reported raw toxicity of the root. The whole plant, but especially the root, is described in ethnobotanical literature as antispasmodic, carminative, diuretic, hypnotic, powerfully nervine, sedative, and stimulant. The seed, where used as food, was parched rather than consumed raw.

Historical Use of the Broader Valeriana Genus

Because V. capitata occupies remote subarctic and alpine regions, documentation of its traditional use is thinner than that for the more widely cultivated V. officinalis. The broader genus, however, carries a long and well-documented record of medicinal use spanning many cultures. The Greek physician Dioscorides recommended valerian root to treat many disorders, including heart palpitations, digestive problems, and insomnia. In the old Germanic world, valerian was hung from doorways to protect the home from evil spirits and used as a fumigant (incense) against witches and devils. During both World War I and World War II, valerian was used to treat shell-shocked troops and calm civilians from the psychological nervous effects of air raids.

Galen recommended valerian for insomnia in the second century. Beginning in the sixteenth century, this herb became popular as a sedative in Europe, and it later became popular in the United States. Scientific studies on valerian in humans began in the 1970s, leading to its approval as a sleep aid by Germany's Commission E in 1985.

Some Valeriana species have been used as traditional medicines, demonstrating calming fright and tranquilizing the mind, promoting Qi and blood, activating blood circulation and regulating menstruation, dispelling wind and eliminating dampness, regulating Qi-flowing to relieve pain, and promoting digestion and checking diarrhea — treating diseases of the nervous, cardiovascular, and digestive systems, and conditions related to inflammation, gynecology, and others.

The most commonly used valerian preparations include aqueous and hydroalcoholic extracts, such as tinctures, intended for oral administration. In addition, ammoniated valerian tinctures were used medicinally in the English-speaking world since at least the beginning of the seventeenth century.

Key Constituents and Phytochemistry

Overview of the Genus

Valeriana capitata has not been the subject of dedicated species-level phytochemical isolation studies in the peer-reviewed literature. The following chemical profile is therefore drawn from the well-characterized genus-level chemistry, augmented by the taxonomically and morphologically close relationship to V. officinalis and other studied congeners.

More than 800 compounds have been isolated or identified from Valeriana, including iridoids, lignans, flavonoids, sesquiterpenoids, alkaloids, and essential oils. Valeriana spp. are well known for their essential oils, iridoid compounds such as monoterpenes and sesquiterpenes, flavonoids, alkaloids, amino acids, and lignanoids.

Iridoids and Valepotriates

The genus Valeriana is rich in iridoids; 306 different iridoids have been listed from plants of Valeriana. Iridoids are by far the major secondary metabolite class of the genus, and mostly non-glycosidic ester iridoids (valepotriates and their derivatives) are reported from this genus. Iridoids are monoterpenic structures with a cyclopentano-pyranoid skeleton. They are generally classified as iridoid glycosides, non-glycosidic iridoids, seco-iridoids, and dimeric iridoids. Although they are small molecules, the structural variations in iridoids are plentiful.

Also present in the drug are epoxy-iridoid esters called valepotriates: for example valtrate, didrovaltrate, acevaltrate, and isovaleroyloxyhydroxydidrovaltrate. The sedative and antispasmodic properties of valerian preparations have been attributed primarily to the presence of chemically labile monoterpenoid iridoid triester compounds called valepotriates ("valerian-oxy-triesters").

Sesquiterpenoids: Valerenic Acid and Relatives

More than 150 different phytochemical compounds have been identified in valerian root, with the main components being sesquiterpenes (e.g., valerenic acid), iridoids, and flavonoids. Iridoids (valepotriates) and sesquiterpenoids (valerenic acids) are recognized as the most important groups of pharmacologically active secondary metabolites characteristic for the roots of valerian. Key sesquiterpenoids include valerenic acid, acetoxyvalerenic acid, hydroxyvalerenic acid, valerenol, and valeronal. Seasonal variations in the constituents of valerian have been reported; the accumulation of valerenic acid and its derivatives together with valepotriates reached a maximum in February to March, whereas the volatile oil remained essentially constant during the period of study.

Notably, of plants of the Valerianaceae family, only V. officinalis L. is known to contain extractable valerenic acid in its roots. This is a pharmacochemically significant distinction: V. capitata, despite its close morphological similarity to V. officinalis, has not been confirmed to contain valerenic acid in published peer-reviewed literature.

Flavonoids and Other Polyphenols

The main compounds found in Valeriana root include alkaloids, terpenes, polyphenolic acids and their derivatives, flavones, and valepotriates. Flavonoids present in various Valeriana species include linarin and 6-methylapigenin, both of which have been studied for their potential GABAergic activity. Lignanoids — including pinoresinol glucoside and related compounds — have also been isolated from valerian species roots.

Alkaloids

Valerian contains alkaloids (approximately 0.05–0.1% in the dried root); these include compounds such as chatinine and valerine described in older literature. Two quaternary alkaloids with a monoterpene structure, similar to skytanthine and related alkaloids, have also been reported.

Essential Oils and Volatile Compounds

The roots and rhizomes of Valeriana spp. are rich in essential oils, iridoids, flavonoids, alkaloids, amino acids, and lignanoids, which possess a characteristic fragrance and are used as medicines based on their inherent bioactivities including inducing sedation, promoting sleep, antidepression, and antianxiety. Characteristic volatile sesquiterpenes include valerenal and kessyl derivatives.

Mechanisms of Action

GABAergic Activity

The most extensively characterized mechanism of action of Valeriana extracts involves modulation of the γ-aminobutyric acid (GABA) neurotransmitter system. Valepotriates and valerenic acid found in valerian root are held responsible for the plant's sedative and anxiolytic effects. The sleep-supporting effect of valerian has been shown to involve the upregulation of gamma-aminobutyric acid A (GABA_A) receptor activity. The valerenic acid contained in valerian inhibits the enzyme system responsible for the catabolism of GABA. Valerian and its constituents (e.g., valerenic acid) serve as GABA agonists, and the effect of the plant on GABA_A receptors is similar to the effect of benzodiazepines.

The constituents of valerian may increase GABA concentrations and decrease central nervous system activity by inhibiting the enzyme system responsible for the central catabolism of GABA. Valerian may also stimulate the release and reuptake of GABA and bind directly to GABA_A receptors.

Research published in Neuropharmacology characterized the binding site in molecular detail: a specific binding site on GABA(A) receptors with nanomolar affinity for valerenic acid and valerenol has been identified. Both agents enhanced the response to GABA at multiple types of recombinant GABA_A receptors. A point mutation in the β2 or β3 subunit (N265M) of recombinant receptors strongly reduced the drug response. In vivo, valerenic acid and valerenol exerted anxiolytic activity with high potencies in the elevated plus maze and the light/dark choice test in wild-type mice. In β3(N265M) point-mutated mice, the anxiolytic activity of valerenic acid was absent. Thus, neurons expressing β3-containing GABA_A receptors are a major cellular substrate for the anxiolytic action of valerian extracts.

In-vitro experiments demonstrated that valerian extracts allosterically modulate GABA-A receptors, an action related to valerenic acid; these results were confirmed with in-vivo rodent studies. However, the relationship among individual constituents is complex: valerenol, 6-methylapigenin, and linarin — other components of the extract — also demonstrate activity at the GABA channel; however, these results were obtained from in-vitro experiments, and confirmation from in-vivo studies is still lacking.

Serotonin and Monoaminergic Effects

Valerian is also considered a partial agonist of the 5-hydroxytryptamine 2A (5-HT_2A) receptor that boosts melatonin release. Antidepressant and mood-stabilizing effects have also been proposed for valerian, which could be due to the plant's ability to interfere with noradrenergic and dopaminergic neurotransmitters, especially serotonin and GABA.

Adenosine Receptor Involvement

Activation of adenosine receptors has been implicated in the action of valerian ingredients. This mechanism may contribute to the plant's observed sleep-promoting and relaxation-inducing properties, since adenosine signaling plays a well-established role in homeostatic sleep pressure.

Cardiovascular Mechanisms

Valeriana spp. exhibit a wide range of biological activities such as lowering blood pressure and heart rate, protection against myocardial ischemia reperfusion injury, antiarrhythmia, and regulation of blood lipid levels. These cardiovascular effects are attributed to multiple compound classes present in the roots and rhizomes.

Enzyme Inhibition Relevant to Metabolic Syndrome

Valerian extract has been shown to inhibit key enzyme activities associated with obesity (lipase), hypertension (angiotensin-converting enzyme/ACE), and type 2 diabetes (α-amylase and α-glucosidase), suggesting that it is a potential candidate for the development of functional supplements. These findings are preliminary and derive from in-vitro enzyme-inhibition assays rather than clinical studies.

Scientific Evidence by Area of Use

Critical caveat: All clinical trials and systematic reviews in this section concern Valeriana officinalis or unspecified Valeriana species, not V. capitata specifically. No published human clinical trials have been conducted exclusively with V. capitata. The evidence below is presented for the genus, and its applicability to V. capitata is inferential, based on documented morphological and phytochemical similarity within the genus.

Sleep and Insomnia

Extracts of the roots of valerian (Valeriana officinalis) are widely used for inducing sleep and improving sleep quality. A systematic review of randomized, placebo-controlled trials of valerian for improving sleep quality identified 16 eligible studies examining a total of 1,093 patients. Most studies had significant methodologic problems, and the valerian doses, preparations, and length of treatment varied considerably.

A dichotomous outcome of sleep quality (improved or not) was reported by 6 studies and showed a statistically significant benefit (relative risk of improved sleep = 1.8, 95% CI, 1.2–2.9), but there was evidence of publication bias in this summary measure.

Three trials investigated the effect of valerian following repeated administration: one methodologically rigorous trial found improvements in various sleep-related parameters; another reported superior sleep latency and duration by 2 weeks; the third (a pilot study) suggested an increase of slow-wave sleep after 1 and 8 days of valerian, but no improvement on other measures. Of the six trials investigating responses to single doses, three reported positive results, while three showed no difference between valerian and placebo — the latter three were all conducted in healthy volunteers without documented sleep problems.

There is not enough evidence to determine whether valerian is useful for any health conditions. The evidence on whether valerian is helpful for sleep problems is inconsistent. In its 2017 clinical practice guidelines, the American Academy of Sleep Medicine recommended against using valerian for chronic insomnia in adults.

Anxiety

Valerian extracts have been used for centuries to alleviate restlessness and anxiety, albeit with an unknown mechanism of action in vivo. Animal studies have demonstrated clear anxiolytic effects, particularly through valerenic acid's interaction with GABA_A β3 subunit-containing receptors. However, translation to clinical human evidence is limited. There is not enough evidence to allow any conclusions about whether valerian is helpful for anxiety, depression, premenstrual syndrome, dysmenorrhea (menstrual cramps), stress, or other conditions.

Menopause Symptoms

Three small studies suggest that valerian might be helpful for menopause symptoms, but there is not enough evidence to know for certain. Research in this area has examined hot flashes specifically, with mixed results across small-scale randomized controlled trials.

Hemodialysis Patients: Sleep, Depression, and Anxiety

A randomized, double-blind, crossover clinical trial evaluated valerian in hemodialysis patients — a population with high rates of sleep disturbance. The study found that a valerian-containing mixture significantly increased non-rapid eye movement sleep time while rapid eye movement sleeping time was decreased; electroencephalography investigation indicated decreased awakening and increased total sleep time. This trial population is highly specific, and results should not be generalized to the broader population without further study.

Cardiovascular Effects

Pharmacology studies on Valeriana have revealed sedative, hypnotic, antispasmodic, analgesic, antidepressant, anxiolytic, anticonvulsant, antiepileptic, neuroprotective, antibacterial, antiviral, cytotoxic, and antitumor effects as well as cardiovascular and cerebrovascular system improvements. The majority of these findings derive from in-vitro and animal studies, and human clinical evidence for cardiovascular outcomes is sparse.

Anticancer (Preclinical Only)

Diene iridoids such as chlorovaltrate, rupesin B, valtrate, and acevaltrate showed cytotoxic activity against metastatic prostate cancer, lung adenocarcinoma, hepatoma, and colon cancer cell lines. These are in-vitro findings in cell culture systems and have not been validated in human clinical trials. No clinical evidence supports the use of Valeriana products for any oncological indication.

Overall Evidence Assessment

Evidence from clinical studies of the efficacy of valerian in treating sleep disorders such as insomnia is inconclusive. Constituents of valerian have been shown to have sedative effects in animals, but there is no scientific agreement on valerian's mechanisms of action. Although few adverse events have been reported, long-term safety data are not available.

Body Systems and Health Areas Associated with Capitate Valerian

Central Nervous System / Neurology: Sedation, sleep support, anxiolytic activity, anticonvulsant and antiepileptic effects (largely preclinical).
Cardiovascular System: Biological activities including lowering blood pressure and heart rate, protection against myocardial ischemia reperfusion injury, antiarrhythmia, and regulation of blood lipid levels.
Digestive System: Carminative and antispasmodic properties attributed to the whole plant, especially the root.
Renal/Urinary: Historically used as a diuretic.
Gynecological/Endocrine: Investigated in small trials for menopause-related hot flashes and dysmenorrhea.
Metabolic: In-vitro evidence suggests inhibition of lipase, ACE, α-amylase, and α-glucosidase activity.

Dosage Forms and Reported Dosages

No species-specific dosing data exist for V. capitata in the scientific literature. All dosage information below pertains to preparations of Valeriana officinalis or unspecified Valeriana as studied in clinical trials.

Common Preparations

Dried root / root powder: Oral capsules or tablets; the most commonly studied form in clinical trials.
Aqueous and hydroalcoholic extracts (tinctures): The most commonly used valerian preparations include aqueous and hydroalcoholic extracts, such as tinctures, intended for oral administration.
Standardized extracts: Products standardized to valerenic acid content, although standardization methods have varied widely across studies.
Incense / dried root (topical/aromatic): The dried root of V. capitata has been used as an incense.

Dosages Reported in Clinical Studies

Doses ranged from 225 mg to 1,215 mg per day across reviewed clinical trials; only 2 of the studies specifically stated that the herb was standardized to a specific amount of valerenic acid.
In one systematic review of randomized clinical trials, doses ranged from 60 to 1,215 mg/day.
A commonly cited typical dosage is 300 to 600 mg at bedtime for sleep, or taken 3 times daily for stress.
Research suggests that valerian is generally safe for short-term use by most adults. It has been used with apparent safety in doses of 300 to 600 milligrams daily for up to 6 weeks.
In one phase 2, randomized, double-blind, parallel-group, placebo-controlled, dose-ranging study, approximately 68 patients were randomized to placebo or a pharmaceutically active extract of valerian at doses of 250, 500, or 1,000 mg/day.

Although there is clearly not enough evidence to define the optimum amount of valerenic acid that should be present in a given dose, the use of standardized products in clinical trials of valerian might improve the reproducibility and clinical relevance of the results. The variation in the dose of valerian in these studies is also reflected in products sold in the United States.

Safety Considerations and Interactions

General Short-Term Safety Profile

Research suggests that valerian is generally safe for short-term use by most adults. It has been used with apparent safety in doses of 300 to 600 milligrams daily for up to 6 weeks. The safety of long-term use of valerian is unknown.

Side effects of valerian include headache, stomach upset, mental dullness, excitability, uneasiness, and vivid dreams. Few adverse events of valerian were reported in clinical trials, and those that were reported were mild and similar to those experienced with placebo.

Withdrawal

Some individuals may experience withdrawal symptoms — including anxiety, irritability, heart disturbances, insomnia, and, in rare cases, hallucinations — if valerian is stopped abruptly after chronic use.

Raw Root Toxicity (Species-Specific Concern)

A safety consideration specific to V. capitata is the reported raw toxicity of the root. The root is reported to be poisonous uncooked. Traditional preparation involving prolonged steaming (documented as 24 hours) appears to be necessary for safe consumption of the root as food. This distinguishes V. capitata from V. officinalis, where dried root preparations are taken directly without cooking.

Liver Toxicity

In very rare cases, liver injury was reported when taking valerian, most often in combination with other herbals; however, valerian's long-term effect on liver function is unknown. Valerian has been implicated in a small number of cases of clinically apparent liver injury, but usually in combination with other botanicals such as skullcap or black cohosh. In view of its wide-scale use, valerian has to be considered a very rare cause of hepatic injury.

CNS Depressant Interactions

Valerian might have additive therapeutic and adverse effects if taken with sedatives, other medications, or certain herbs and dietary supplements with sedative properties. These include benzodiazepines such as Xanax®, Valium®, Ativan®, and Halcion®; barbiturates or central nervous system depressants such as phenobarbital (Luminal®), morphine, and propofol (Diprivan®); and dietary supplements such as St. John's wort, kava, and melatonin.

A 1995 study was somewhat reassuring, finding no interaction between alcohol and valerian; however, animal studies have found that valerian extracts may prolong the effects of some sedatives, and some case reports suggest that combining valerian and alcohol can lead to excessive sedation in some people.

Perioperative Risk

Valerian and kava may potentiate anesthetic agents, prolonging sedation recovery. Surgical patients are therefore generally advised to disclose all herbal supplement use prior to procedures.

Populations with Insufficient Safety Data

Safety among young children, pregnant or nursing women, and those with severe liver or kidney disease has not been established. If you have liver disease, avoid taking valerian.

Pharmacokinetic Interactions (CYP Enzymes)

A 2014 review in Evidence-Based Complementary and Alternative Medicine examined the interaction potential of valerian root in detail. In widely used information websites directed to cancer patients, valerian is claimed to have a potential for adverse interactions with anticancer drugs, which questions its use as a safe replacement for, for example, benzodiazepines. However, the review's overall assessment found that formal clinical pharmacokinetic studies provided insufficient evidence of clinically relevant CYP-mediated interactions at commonly used doses, and that the interaction claims were largely theoretical.

Pharmacopeial Status

Valeriana spp. are now listed in the European and USA pharmacopeias, and the genus is one of the highest selling natural medicines in Europe and the USA. These listings, however, refer to V. officinalis as the official drug plant; V. capitata is not independently listed in major pharmacopeias or pharmacopeial monographs as of the available literature.

Research Gaps and Summary Assessment

Valeriana capitata occupies a distinct ecological niche (Arctic and high-altitude habitats of Siberia, Central Asia, and subarctic North America) and has a documented local ethnobotanical history as a sedative and diuretic. Its morphological and phytochemical kinship to V. officinalis and other studied species makes it reasonable to infer a broadly analogous bioactive profile. However, the following critical research gaps exist:

No peer-reviewed phytochemical analysis of isolated V. capitata material has been published confirming or quantifying specific constituents (valepotriates, valerenic acid, flavonoids).
Only V. officinalis L. is documented to contain extractable valerenic acid in its roots, and the presence or absence of this compound in V. capitata has not been independently verified in published literature.
No human clinical trials have been conducted using V. capitata specifically.
The claim that the raw root is poisonous, while consistent across several ethnobotanical sources, has not been characterized mechanistically in toxicological literature.
At present, the developed drugs from Valeriana are far from sufficient. To effectively promote the utilization of resources, more Valeriana species as well as their different medicinal parts should be the focus of future related studies.

The overall evidence base for the genus-level activity (sedation, anxiolysis, sleep quality) is characterized as inconsistent and methodologically limited at the level of human clinical trials, and as substantially more robust at the level of in-vitro and animal pharmacology.

References

Health Conditions

Health conditions that Capitate valerian may help support.

No conditions available.

Body Systems

Body systems that Capitate valerian may help support.

No body systems available.