- Garden valerian
- Indian valerian
- Pacific valerian
- Mexican valerian
For Patients & Caregivers
How It Works
Valerian may provide modest improvements in sleep, but study results are mixed.
In laboratory experiments, valerian extract prevents the breakdown of an important inhibitory neurotransmitter chemical in the nervous system, causing a calming effect. Human studies suggest valerian products have a modest effect to improve sleep quality. Valerian supplements often have a distinct odor that some may find unpleasant, and these products might interact with a number of drugs or health conditions. More research is needed to determine the benefits and safety of this botanical.
To treat anxiety
Several analyses have determined there is not enough evidence to determine whether valerian can treat anxiety.
To treat insomnia
It is possible that valerian may provide modest improvements in sleep quality. Although a study in cancer patients did not find this to be true, valerian did appear to improve other symptoms such as fatigue, how long it took to fall asleep, and quantity of sleep per night.
To calm muscle spasms
Laboratory studies suggest positive effects, and an initial study indicates that valerian may be helpful for menstrual cramps.
To treat menopausal symptoms
A few studies have shown that valerian may improve hot flashes and insomnia in postmenopausal women.
- Valerian should be stopped at least 1 week before surgery because it can interfere with general anesthesia.
- Patients should not drive or operate dangerous machinery after taking valerian because it could disrupt the ability to process information, perform tasks, or be alert.
- Withdrawal symptoms may occur in those taking valerian for a period of time, if valerian is discontinued abruptly.
Do Not Take If
- You are taking barbiturates, benzodiazepines, or other central nervous system drugs used to treat conditions such as anxiety, insomnia, seizures, or psychiatric disorders: Valerian lengthens the sedation time caused by these drugs and may have other added effects.
- You are taking haloperidol: Valerian may increase effects and cause liver damage.
- You are taking drugs that are substrates of P-glycoprotein: Valerian may increase the risk of side effects of these drugs.
- You are taking drugs that are substrates of cytochrome P450: Valerian may increase the risk of side effects of these drugs.
- You have pancreatic, liver, or gall bladder disease: Valerian usage has been associated with cases of liver damage and acute infection of the pancreas.
- You are driving or operating machinery: Valerian may affect your performance or functioning.
- You are pregnant or nursing: Animal experiments have shown reduced levels of essential micronutrients in fetal mouse brain tissue.
For Healthcare Professionals
Derived from the root of the plant V. officinalis, valerian is sold as a dietary supplement for calmness, sedation, and to improve sleep quality. Other species including V. jatamansi, V. fauriei, and V. wallichii are also used in traditional medicine to treat insomnia and anxiety. Valerian products are usually available in extracts or teas that have a distinct odor.
In vitro, valerian exhibits antioxidant (1), cytoprotective (2), and neuroprotective (3) effects. In animal models, valerian has demonstrated antihypertensive, antispasmotic (4) (5), anxiolytic (6), and antidepressant (7), but not sedative (8) effects. Human studies show that valerian has modest effects on improving sleep quality (9) (10) (11), but its sleep-inducing properties are not superior to placebo (12) (13) (14) (15). Valerian also failed to improve sleep in a study of cancer patients (16). Other studies suggest that valerian can improve sleep and anxiety in HIV patients on antiretroviral therapy (53), reduce hot flashes (17) (54) and dysmenorrhea (18), facilitate supervised benzodiazepine withdrawal (19), and relieve symptoms of obsessive-compulsive disorder (20). However, sample sizes in these studies are too small to draw firm conclusions. Reviews of the clinical literature have also concluded the evidence for valerian as an anxiolytic in humans is insufficient (21) (22).
The valerian derivative isovaleroxy-hydroxy dihydrovaltrate showed anticancer effects against human ovarian cancer cells in vitro and in vivo (23). Chlorovaltrates in valerian have shown moderate cytotoxicity against lung, prostate, colon and liver cancer cell lines (24). However, no clinical trials on these effects have been conducted.
Although valerian products are generally safe, cases of liver and pancreatic toxicity have been reported (25) (26) (27). Valerian inhibits CYP3A4 enzymes and P-glycoprotein transporters and is prone to interact with many drugs (27). Valerian is also thought to have estrogenic activities (17) (28), but this is not observed in vitro (29).
Mechanism of Action
In vitro, valerian protects against lipid peroxidation, deoxyribose degradation, and reactive oxygen species production (1). Iridoids, germacrane-type sesquiterpenoids, and lignans in valerian are associated with neuroprotective effects (3) (34). Valerian constituents can also bind to various neurotransmitter receptors implicated in circadian rhythms and anxiety such as serotonin receptors (35). In vitro and animal models indicate that anxiolytic activity is due to valerenic acid (VA) which could be inhibited by VA derivatives such as hydroxy-VA that do not modulate gamma-aminobutyric acid type A (GABAA) receptors (36). VA in animals inhibits the enzyme system responsible for central catabolism of GABA, increasing GABA concentration and decreasing CNS activity, and direct binding of this constituent to GABA-receptors has been demonstrated (37). VA interaction with the GABAAergic system has been noted to act in a manner similar to that of benzodiazepines (6). Sesquiterpenes and valepotriates were identified as having varying levels of antidepressant activity (7) (38). Chronic treatment of rodents with valepotriate-rich extract increased norepinephrine and dopamine levels (38). Valerian exhibits antispasmodic and hypotensive effects via potassium channel (KATP) activation, which may be useful in gastrointestinal and cardiovascular disorders (5). Valerian also exhibited a protective effect against vasopressin-induced coronary spasm and pressor response, suggesting coronary and systemic vasodilation (4).
In healthy volunteers, valerian was found to modulate intracortical facilitatory circuits (55). Valerian iridoids may have choleretic activity and this may increase the risk of gallstone formation, and therefore explain the increased risk for development of acute pancreatitis (27).
- Valerian should be discontinued at least 1 week before surgery because it may interact with anesthesia (40) (41).
- Patients should not drive or operate dangerous machinery after taking valerian as it could disrupt information processing, task performance, and vigilance (35).
- Abrupt discontinuation of valerian in those who may have developed a dependency may cause benzodiazepine-like withdrawal (40).
- Patients with liver or pancreatic disease should avoid valerian as there have been case reports of hepatotoxicity (25) (26) as well as a possible association of valerian iridoids with an increased risk for development of acute pancreatitis (27).
- Patients should not drive or operate dangerous machinery when taking valerian as early studies indicate that single-dose valerian could disrupt information processing, task performance, and vigilance in humans 1–2 hours post-administration (35).
- Individuals who are pregnant or nursing should avoid valerian, as it has not adequately been studied and preliminary animal models indicate some adverse effects on fetal brain development (42).
Occasional, anecdotal, or possibly related: Headache, diarrhea and other gastrointestinal complaints, daytime sedation/dullness, impaired alertness, depression, irritability, dizziness, sweating, heart palpitations, bitter taste, benzodiazepine-like withdrawal symptoms with supplement cessation (10) (16) (35) (43).
Hepatotoxicity: Two separate cases in women with the use of valerian products, with eventual symptom resolution after discontinuation (25) (26).
Risk of acute pancreatitis: A case-control study identified valerian use as a potential contributor to cases of idiopathic acute pancreatitis (27).
Fetal development: Valerian administration in pregnant mice significantly reduced zinc levels in the fetal brain (42).
Barbiturates: Valerian prolonged pentobarbital-induced sleep in animal models (40) (44).
Benzodiazepines: Valerian may have synergistic effects (45) (46).
Haloperidol: Valerian may have an additive effect, causing hepatic damage (47).
Cytochrome P450 (CYP450) substrates: Valerian inhibits CYP2D6 (48) and CYP3A4 (41) (49), and can affect the serum concentration of drugs metabolized by these enzymes.
P-glycoprotein (P-gp)substrates: Valerian inhibits P-gp transporters and can increase the intracellular concentration of substrate drugs (17) (28) (49).
UGT (Uridine 5’-diphospho-glucuronosyltransferase) substrates: Valerian modulates UGT enzymes in vitro and can increase the side effects of drugs metabolized by them (50).