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From The November 2000 Issue of Nutrition Science News
Valerian Root Is a Safe Sedative
by the American Herbal Pharmacopoeia
Valerian (Valerian officinalis) has been used medicinally for at least 2,000 years. It was included in many editions of the United States Dispensatory (Merck) since 1849, which reported the herb's effect on the nervous system and its ability to produce drowsiness and sleep.1
Various valerian species are still included in the pharmacopoeiae of many nations including Belgium, France, Germany, Italy, Switzerland and the United Kingdom. The United States Pharmacopeial Convention has accepted a valerian monograph for inclusion in the National Formulary (Pharmacopeial Forum, 1998). It is widely used as a sedative and antispasmodic in the United States. Valerian preparations appear to be candidates for safe and effective nonaddictive alternatives to conventional sleep medications.
Valerian roots contain several compounds with demonstrable pharmacological activity. These include the essential oil and its sesquiterpenoids (valerenic acid), epoxy iridoid esters (valepotriates) and their decomposition products such as baldrinal and homobaldrinal, amino acids (arginine, GABA, glutamine, tyrosine) and alkaloids. Valerian also contains small amounts of phenolic acids, flavonoids, valerosidatum, chlorogenic acid, caffeic acid, choline, B-sitosterol, fatty acids and various minerals.
Valerian analyses have primarily focused on the essential oil, valerenic acid and valepotriates. In the United States, the essential oil and valerenic acid are commonly used as marker compounds for qualitative and quantitative analysis of valerian root and valerian products.
The only pharmacokinetic data available for valerian are regarding the valepotriates. The clinical relevance is largely inconsequential since valepotriates rapidly degrade in commercial products. Although metabolic by-products of valepotriates are considered more active than the valepotriates themselves, these are similarly not present in commercial products.
Research into valerian's pharmacological activity has focused almost exclusively on its sedative and spasmolytic properties. Individual components have displayed activity, but no single constituent has accounted for valerian's total action.
Effect on Sleep
Several clinical studies have been conducted on valerian's effects, each using the same aqueous herbal extract. This preparation, made with deionized water heated to 60°C and subsequently freeze-dried, reportedly contained only trace amounts of valepotriates (0.01 percent).
The first of these studies, in 1982, was a double-blind clinical trial wherein 128 subjects received one of three samples: either an aqueous valerian extract, a commercial preparation containing extracts of valerian and hops strobiles (2:1 ratio) or placebo. Both valerian preparations contained 400 mg valerian extract, the dose recommended in the Swiss pharmacopoeia. Subjects, through questionnaires, reported a reduction in sleep latency and an increase in sleep quality compared with placebo. People who considered themselves poor or irregular sleepers obtained the most benefit. The commercial preparation was not as effective as the extract. Neither preparation had an effect on night awakenings or dream recall.2
In a subsequent double-blind, placebo-controlled study, eight volunteers with mild insomnia were given 450 mg or 900 mg valerian extract. Sleep onset was determined by reduction in body movement as measured by wrist-worn activity monitors. Sleep onset was accelerated from an average of 15.8 minutes (+/ 2.2 minutes) to 9.0 (+/ 1.5) minutes. The higher dose did not enhance sleep more than the 450 mg dose. Valerian extract did not influence total sleep time or normal levels of movement during the night. The authors concluded that valerian was at least as effective as small doses of barbiturates or benzodiazepines.3
In another study, 80 elderly patients with behavioral disorders of nervous origin, including difficulty falling asleep, difficulty sleeping through the night and rapid fatigue caused by impaired sleep, were evaluated in a placebo-controlled study. Patients were given either placebo or six tablets daily of Valdispert, a product containing 45 mg dry valerian extract standardized to 0.05 mg valerenic acid and acetoxyvalerenic acid. Subjects were assessed based on objective (NOSIE) and subjective (von Zersenn's well-being scale) parameters. Researchers observed significant improvements in subjects' ability to fall asleep and sleep through the night and a decreased level of fatigue after 14 days of treatment. The medication was well tolerated.4
In two large, uncontrolled multicenter trials, patients experiencing functional sleep disturbances and anxiety reported subjective improvement after treatment with the valerian preparation Baldrian-Dispert (corresponding to Valdispert) for 10 days. In the more recent of the two studies, 1,689 patients, both children (average age of 10) and adults (average age of 48), took from three to nine tablets per day. Each tablet contained 45 mg dry valerian extract. Subjects noted improvement in sleep and ability to concentrate in the first two days of treatment, and increasing improvements on subsequent days. Fifty percent of those patients whose primary complaint was difficulty in concentration reportedly were symptom-free within the 10-day period. Subjects also experienced reduction of other symptoms, including cardiac palpitations, depression and menopausal neurosis. Only eight patients reported side effects including gastrointestinal upset and headache.5
Similar results were reported in a study of 11,168 patients treated by 982 German practitioners. Symptoms were eliminated in 70 percent of subjects and improved in another 24 percent—only six percent of patients remained unchanged.6
In summary, studies demonstrate statistically significant decreases in sleep latency and increases in sleep quality for poor sleepers. No change has been reported in night awakenings, dream recall, total sleep time, or the normal levels of movement during the night.
Safety Profile
In sensitive individuals, valerian can cause heart palpitations and nervousness. Occasional headache and gastrointestinal distress were reported in one clinical study.5 According to the older herbal literature, excessive doses or large continuous doses may cause nausea, diarrhea, headache, agitation and heart palpitations, and dull senses and response times.7,8
Because benzodiazepines taken to aid sleep can impair alertness the morning after, researchers wanted to see whether this would also be the case with valerian preparations. In a placebo-controlled study, four groups of 20 healthy volunteers were treated with tablets containing valerian and hops, a syrup containing only valerian, 1 mg flunitrazepam or placebo. Only the flunitrazepam group experienced an objectively measurable performance impairment the morning after medication. Subjects taking valerian and hops tablets and valerian syrup showed improvement according to subjective self-assessment (more alert, more active, subjective feeling of well-being).9
Valerian and some valerian preparations have been shown to potentiate the effects of barbiturates.10 As with other sedatives, anyone using valerian in the daytime should take care while driving, if operating heavy machinery or if engaged in activities requiring mental alertness. Because valerian is considered to work in a manner similar to benzodiazepines, abrupt discontinuation after long-term use can cause withdrawal symptoms.11
There have been no reports of chronic toxicity when valerian is used at recommended therapeutic doses. At daily doses of 400600 mg/kg for 45 days in rats, no significant changes in weight, blood or urine were observed when compared with controls.12 Oral doses of an alcohol extract equivalent to 300 and 600 mg/kg did not affect growth, arterial pressure or weight of key organs, and did not alter hematological or biochemical parameters.13
Finally, several reports have associated valerian consumption with hepatotoxicity. The effects may have been idiosyncratic because a range of doses were used in the studies and because higher doses of valerian have not been implicated.14 It is not clear whether these findings may be related to the type of extract used or different formulations.
Sidebars:
Valerian: Substantiated Structure/Function Claim
Excerpted with permission from American Herbal Pharmacopoeia and Therapeutic Compendium, a bimonthly series of peer-reviewed monographs. Complete monographs are available individually or by subscription and are published by the American Herbal Pharmacopoeia, Santa Cruz, Calif.
References
1. Wood GB, Vache F. The dispensatory of the United States of America. 8th ed. Philadelphia: Grigg, Elliot; 1849. p. 1,380.
2. Leatherwood PD, et al. Aqueous extract of valerian root (Valerian officinalis L) improves sleep quality in man. Pharmacol Biochem Behav 1982;17:65-71.
3. Leatherwood PD, Chauffard F. Aqueous extract of valerian reduces latency to fall asleep in man. Planta Med 1985;51:144-8.
4. Kamm-Kohl AV, et al. Modern valerian therapy of nervous disorders in elderly patients. Medwelt 1984;35:1450-4.
5. Siefert T. Therapeutische effekts von Baldrian bei nervosen Storungen. Klinik Praxis Therapie 1988;2:94-8.
6. Voight-Schmidt J. Treatment of nervous sleep disturbances and inner restlessness with a purely herbal sedative: results of a study in general practice. Therapiewoche 1986;36:663-7.
7. Culbreth DMR. A manual of materia medica and pharmacology. 6th ed. Portland (OR): Eclectic Medical Publishing; 1917. Reprinted: 1983 p. 627.
8. Felter HW, Lloyd JU. King's American Dispensatory. Vol. 1. 18th ed. Portland (OR): Eclectic Medical Publishing;1898. Reprinted 1983 p. 2, 172.
9. Gerhard U, et al. Vigilance-decreasing effects of 2 plant-derived sedatives. Schweiz Rundsch Med Prax 1996 Apr;85(15):473-81.
10. Bounthanh D, et al. Observation on effects of galenic valerian preparations (Valeriana officinalis) on the behavior of mice. Planta Med 1980;39:241.
11. Garges HP, et al. Cardiac complications and delirium associated with valerian root withdrawal. JAMA 1998;280(18):1566-7.
12. Rosecrans JA, et al. Pharmacological investigation of certain Valeriana officinalis L extracts. J Pharm Sci 1961;50(3):240-4.
13. Fehri B, et al. Valeriana officinalis et Crataegus oxyacantha: toxicite par administrations reiterees et investigations pharmacologiques. J Pharmacol 1991;46:165-76.
14. Shaw D, et al. Traditional remedies and food supplements: a 5-year toxicological study (1991-95). Drug Safety 1997;5:342-56.
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