Valerian Root (Valeriana officinalis)

Indications

Insomnia and possibly nervousness and anxiety.

Mechanism of Action

Several constituents of Valeriana officinalis have been found to have sedative or anxiolytic properties. These constituents are valerenic acid (VA), 6-methylapigenin (MA), (2S)-hesperidin (HN), and the flavonoid glycoside linarin (LN). VA and MA have been shown to have GABAergic activity. The mechanism by which LN and HN has a sedative effect is still unknown, but it does not seem to be via GABAergic pathways.

When administered simultaneously, LN and VA have been shown to act synergistically,¹ as have MA and HN.² The sedative and soporific effects of Valeriana officinalis therefore can likely be attributed to the activity of at least the four constituents LN, HN, MA, and VA plus their potentiating effects when the whole root is used.¹

Evidenced-Based Research

Research literature contains a fair amount of positive evidence for using V. officinalis to treat insomnia, but not to treat acute and chronic anxiety. One study investigated the use of an aqueous solution of V. officinalis to enhance sleep quality in male participants (n=128). The best results were experienced by men who were more than 40 years old, and those who rated themselves as poor or irregular sleepers who thought they had long sleep latencies. In that group, a 3:1 extract of V. officinalis was associated with a significant decrease in sleep latency scores and improvement in sleep quality. Dream recall, sleepiness the next morning, and night awakenings were unaffected.³

A 2011 article examined studies of V. officinalis published between January 2000 and March 2010, in English, Spanish, French, and Portuguese. The authors’ search criteria turned up 173 articles, but only four (a meta-analysis, a systematic review, a randomized controlled trial for using V. officinalis in sleep disorders, and a systematic review for its use in anxiety disorders) were found to be of sufficient quality to be included in the review. The authors concluded there was insufficient evidence to recommend using V. officinalis for anxiety, but good evidence for its use with insomnia. They also concluded from the evidence that V. officinalis root is safe and generally well tolerated.⁴

Safety in Pregnancy and Breastfeeding

In two studies of pregnant rats, very high doses of V. officinalis were administered for 7 days during the gestational period. One study used doses up to 2.7 g/kg, which is 65 times higher than the normal human dose. This study found no signs of maternal toxicity, and no observable adverse effects on fetal development.⁵ The second study, which used doses of 2.8 g/kg, found a reduction in placental weight, but not in birth weight.⁶

No concern is noted in traditional use for nursing mothers using V. officinalis.⁷ However, no evidence base currently exists regarding its use during lactation.

General Safety

A meta-analysis of 16 randomized, placebo controlled trials (totaling 1093 patients) demonstrated a high degree of safety with oral administration of V. officinalis root. With the exception of a single study, adverse events were either not observed or were similar to placebo. The exception was a study where the treatment group had a significant increase in diarrhea compared with controls.⁸

Idiosyncratic, stimulant-like reactions have been reported anecdotally. One source estimates that 2%–3% of the population is susceptible to stimulant-like effects such as increased heart rate and agitation.⁹

Dosage

Most studies of safety and efficacy use a time frame of up to 30 days and a dose of 400–900 mg around 2 hours before bedtime. Taking 300–450 mg daily of a V. officinalis extract in three divided doses has also been shown to be safe and effective.¹⁰

Traditional Uses

Valeriana officinalis is native to Europe and western Asia; it was introduced into the United States and Canada. The genus name comes from the Latin valere, which means to be strong and healthy.¹¹ The ancient Greek used it to treat insomnia, among other conditions.¹²