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Valeriana officinalis, also known as valerian, is an herb that can be taken as a tea or a supplement. It is commonly used for its sedative and anxiety-reducing effects.
Valerian is most often used for
Last Updated:December 11, 2023
Valerian is a perennial plant in the Valerianaceae family, native to Europe and Asia but also found in North America. Valerian is known for its characteristic fetid odor, which is attributed to the decomposition of valepotriates,[2] one of the principal types of bioactive compound found in valerian. There are more than 250 species of valerian, including Valeriana edulis, Valeriana wallichii, and Valeriana fauriei. Valeriana officinalis is the species most commonly found in supplements, and it’s the only species that will be discussed on this page.[4]
Valerian’s sedative properties have been acknowledged in Europe since the 18th century,[5] and today, the European Medicines Agency (EMA) recommends its use for the relief of sleep disorders (e.g., insomnia) and to alleviate mild nervous tension. In the United States, valerian is considered a dietary supplement rather than a medication, and is regulated by the Food and Drug Administration (FDA).[2][3]
Valerian supplements are commonly used to address sleep disorders (e.g., insomnia) as an alternative to conventional medications. Research has shown that supplementation with valerian may improve subjective sleep quality when compared to placebo. However, its effectiveness has not yet been demonstrated through quantitative or objective measurements (e.g., sleep latency time, visual analogue scales).[5][6] Other randomized controlled trials (RCTs) have noted that valerian may have therapeutic applications beyond treating insomnia, such as brain and menstrual health.
Valerian is generally regarded as highly safe, with few side effects reported that are significantly different from those experienced with a placebo.
One meta-analysis noted a notable increase in the occurrence of diarrhea.[5] Other side effects, such as nausea, epigastralgia (pain in the upper middle part of the abdomen), or heartburn, have been reported in some studies, but no significant difference was found between the intervention and the placebo group.[5]
Regarding adverse effects on the central nervous system, one study reported somnolence as a negative side effect when valerian was taken at night.[7] However, one meta-analysis found that while studies of valerian supplementation reported mild headache, nervousness, and drowsiness as side effects, these side effects weren’t significantly different from those experienced by participants who received a placebo.[5] Furthermore, valerian does not appear to impair cognitive or psychomotor functions in either healthy adults or the elderly, and no side effects were observed when valerian was taken for insomnia by either postmenopausal women or older women. Valerian also seemed to be safe when consumed by children between 7 and 14 years old with sleep problems and cognitive deficits, although this study only included 5 participants.[2]
Some of the studies included in one meta-analysis did report mild side effects, including vivid dreams, fatigue, dizziness, sleepiness, drowsiness, and depression. However, it was not possible to establish a causal relationship between the treatment with valerian and these adverse effects.[2]
Finally, valerian does not appear to interfere with the expression of enzymes of the cytochrome P450 (CYP) family, suggesting that the likelihood of a drug-supplement interaction with medications metabolized by this enzyme group is low.[2] Nonetheless, further research is required to explore potential interactions in more depth.
Valerian contains numerous active compounds which may be responsible for its properties. The essential oil of the root includes valerenic acid (valerian’s main bioactive component), monoterpenes (e.g., borneol, bornyl acetate), and other sesquiterpenes (e.g., valeric acid, isovaleric acid). The root also contains iridoid valepotriates (esters of short-chain fatty acids), lignans, volvalerenone A (a sesquiterpene),[8] and flavonoids.[2]
In vitro studies indicate that valerenic acid and valerenol may modulate gamma-aminobutyric acid (GABA) receptors by stimulating the GABA response in the nervous system.[2] This mechanism of action may underlie valerian’s sedative and anxiolytic effects.[5] However, significant GABAergic signaling after oral ingestion of valerian in humans has yet to be confirmed.
Additionally, in vitro research suggests that some components of valerian extract may also influence the serotonergic system due to their partial affinity for specific 5-HT (serotonin) receptors in the brain responsible for regulating the circadian rhythm.[2] Further research is required to substantiate these findings.
Finally, studies have observed an increase in the slow-wave sleep (SWS) phase (also known as the deep-sleep stage) following valerian supplementation.[9][10] This may explain why some studies reported an improvement in subjective sleep quality, while not demonstrating changes in other objective sleep measurements.[2]
For the treatment of insomnia, studies have found that valerian root extract should be taken in doses ranging from 300 to 600 mg daily, equivalent to 2 to 3 grams of dried herbal valerian root soaked in one cup of hot water for 10 to 15 minutes. Valerian works better when taken 30 minutes to two hours before bedtime.[1]
The European Medicines Agency recommends valerian root to relieve nervous tension, at a dosage of 400–600 mg of valerian extract or 0.3–3 g of powdered valerian root up to 3 times daily.[2][3]
Full page update
We updated this page and it's database with the newest meta-analyses.