Valerian root may not be an actual sleep promoter as we once thought, but does it have other important benefits? Surprising facts are presented that may cause a rethink on the uses and side effects of valerian.
What is Valerian?
Valerian (Valeriana officinalis), also known as all-heal or garden heliotrope, is a flowering plant native to Europe and parts of Asia. Since ancient times, the root of this plant has been used to treat insomnia, nervousness, trembling, headaches, and heart palpitations .
Valerian flowers have a delicate scent once used in perfumes. Valerian root, however, has a very strong, earthy smell. This is because of the volatile oils and other compounds responsible for its sedative effects [2, 3].
There are over 250 species of valerian, but V. officinalis is the species most used in the West .
Of the others, only 2 are commonly used medicinally (Himalayan V. wallichii and Mexican V. edulis). All differ chemically .
Valerian supplements are made from the plant’s roots and stems. They are consumed in various forms, including teas, tinctures, capsules, and tablets .
This article focuses on Valeriana officinalis.
Three main chemicals are thought to be the active components of valerian: The essential oils (valerenic acid and valenol), valepotriates, and a few alkaloids, (actinidine, chatinine, shyanthine, valerianine, and valerine) [10, 4, 11, 12].
Compounds in Valerian Root Responsible for Anti-Anxiety/Sedating Effect Include:
- Valerenic acid increases levels of GABA, a neurotransmitter that reduces brain cell activity. It also has anti-inflammatory effects (by reducing NF-KappaB activity) [13, 14, 15].
- Iridoids (valepotriates and their derivatives) have sedative effects, but are unstable and break down during storage or in water, making their activity difficult to assess [11, 12, 16].
- Isovaleric acid prevents involuntary muscle contractions. Its action is similar to valproic acid, which is used to treat epilepsy .
- Hesperidin and linarin are antioxidant flavonoids with sleep-enhancing effects. Hesperidin also has anti-seizure effects (by blocking calcium channels) [18, 19, 20].
GABA is also found in valerian extracts in quantities sufficient to cause a sedative effect, although it is not known whether it crosses the blood-brain barrier. However, the glutamine present in water (but not alcohol) extracts of valerian root can cross the blood-brain barrier and be converted to GABA [21, 22].
Mechanisms of Action
Valerian Root Increases GABA in the Brain
Most of the valerian’s effects are attributed to the interaction of its constituents with the GABA receptor .
Valerenic acid in valerian increases brain levels of gamma-aminobutyric acid (GABA), which slows down nerve activity in the brain. It does this by binding to GABA receptors in the amygdala, the region of the brain involved in fear and emotional responses to stress. This produces a calming effect similar to benzodiazepines (anti-anxiety drugs), which is why valerian has been called “nature’s valium” [29, 14].
It also increases GABA in the brain by:
- Preventing GABA from being taken back into nerve cells [30, 21, 31, 14, 32]
- Inhibiting the breakdown of GABA by enzymes (GABA aminotransferase and succinic semialdehyde dehydrogenase) [22, 33, 30, 34]
Valerian Root Activates Adenosine Receptors
The lignan fraction of valerian activates specific A1 adenosine receptors, which are involved in promoting sleep .
Valerian Root Binds to Serotonin Receptors
Valerian Root Inhibits Prostaglandin
Valerian prevents excessive smooth muscle contraction by inhibiting the release of prostaglandins. This accounts for its effectiveness in reducing painful uterine cramps during menstruation. It does this by the action of valepotriates, although the mechanism is not fully understood [1, 39].
Valerian Root Relaxes Blood Vessels
Valerian widened blood vessels in cats .
Valerian Root May Reduce Cortisol Levels and Oxidative Damage
Valerian prevents memory loss and improves nerve cell production and development in mice by reducing corticosterone levels (mouse equivalent of cortisol) and preventing oxidative damage in the memory center of the brain (hippocampus) .
Valerian Root Is Anti-Inflammatory
1) Valerian Root May Improve Sleep
In a 2-day study of 27 elderly patients with mental problems, 44% reported perfect sleep and 89% reported improved sleep using a valerian preparation (containing sesquiterpenes) .
Additionally, one-month-long study (DB-RCT) of 16 people with insomnia found that a single dose of valerian improved the time to achieve deep sleep and duration of deep sleep .
Valerian also helps reduce sleep disturbances in a variety of health conditions:
One of the valerian’s main effects appears to be reducing sleep latency, or the amount of time it takes to fall asleep. A study in mice found that valerian decreased the time needed to go to sleep, rather than improving sleep quality .
However, a more recent meta-analysis (18 RCTs and over 1,000 patients) found that valerian’s improvement of insomnia was subjective, with no objective measurements demonstrating its effectiveness [56, 47].
A later 6-day study in 16 sleep-disturbed participants also found that valerian treatment was ineffective for short-term sleep problems .
While some research shows that valerian may be useful for treating short-term insomnia, there is a lack of well-designed clinical trials that support its effectiveness and safety beyond 4 to 6 weeks [58, 56, 46, 54, 58, 59].
Rather, its main benefit seems to be promoting natural sleep after several weeks of use, without risk of dependence or negative health effects. When used properly, it can serve as a more gentle alternative to common insomnia drugs like benzodiazepines in patients with long-term sleep disorders [60, 49, 61].
2) Valerian Root May Reduce Anxiety
One study of 2,462 adults with major depressive disorder and anxiety found that high doses of valerian (1000 mg/day) taken in combination with St John’s Wort (600 mg/ day) for 6 weeks reduced symptoms of anxiety and depression by 66% .
Similarly, mice treated with valerian and valerenic acid exhibited a decrease in anxious behaviors .
However, one 4-week pilot study of 36 people with anxiety showed no significant differences between the valerian-treated group and placebo group .
3) Valerian Root May Improve Stress Management
In a study of 27 patients regularly kept awake at night by stress-related intrusive thoughts, 89 % of those patients had better sleep after 1 month of valerian treatment .
Valerian may also reduce physical reactions during stressful situations. Valerian slowed heart rate (compared to kava and control) and reduced blood pressure (compared to control) in response to stress in a 2-week study of 56 healthy people .
A 4-day study of 24 healthy volunteers found that the combination of lemon balm and valerian improved laboratory-induced stress scores at 600 mg compared to placebo, but increased anxiety at a higher dose (1800 mg) .
Valerian reduced physical and psychological stress in rats by maintaining serotonin and norepinephrine levels in brain regions associated with fear and anxiety (hippocampus and amygdala). Deficiencies of these neurotransmitters are linked to depression and anxiety disorders [71, 72, 73, 74, 75].
4) Valerian Root May Improve Hyperactivity and Focus in Children with ADHD
Valerian increases GABA levels in the brain. Deficiencies in GABA causes anxiety, restlessness, and obsessive behavior, which are symptoms often seen in ADHD .
A pilot study (RTC) of 30 children aged 5 to 11, given valerian 3 times a day for 2 weeks, reported improved ADHD symptoms (sustained inattention and impulsivity and/or hyperactivity). These positive effects disappeared 1 week after discontinuing valerian treatment .
In a 7-week study of 169 children under 12 with hyperactivity and concentration difficulties (but not meeting ADHD criteria), the combination of valerian and lemon balm decreased symptoms of restlessness, concentration difficulties, and impulsiveness .
Similarly, another study of 918 children under 12 with difficulty falling asleep and restlessness found that a combination of valerian and lemon balm improved symptoms in 81% of the patients with insomnia and 70.4% of the patients with restlessness without any negative effects after 4 weeks .
5) Valerian Root May Reduce Menstrual Cramp Pain
Valerian can suppress muscle spasms. It inhibits human uterine muscle contractions in cell-based studies .
Because of this, it is commonly used to treat uterine cramping associated with painful periods .
A 3-day study (DB-RCT) of 100 female students found that valerian was effective in relieving menstrual cramp pain compared to placebo .
6) Valerian Root May Decrease Menopausal Symptoms
In a study (RCT) of 100 menopausal women with poor quality sleep, 30% of participants receiving valerian reported higher quality sleep after 4 weeks .
Another 3-month study (DB-RCT) of 60 postmenopausal women found that valerian significantly improved the severity and frequency of hot flashes [82, R].
7) Valerian Root May Improve Heart Health
8) Valerian Root May Ease Restless Leg Syndrome (RLS)
An 8-week study (DB-RCT) of 37 people with restless leg syndrome (RLS) found that valerian significantly improved RLS symptoms and decreased daytime sleepiness .
9) Valerian Root May Improve Well Being During Cancer Therapy
An 8-week study of 227 patients undergoing cancer therapy did not support the use of valerian for insomnia, although fatigue was reduced .
Additionally, in a review, valerian improved insomnia and well being in people undergoing treatment for cancer due to its calming effects. Contrary to popular belief, it did not interact with cancer drugs .
10) Valerian Root May Reduce Frequency of Seizures in Epilepsy
Valerian reduced the frequency of seizures in rats (possibly by activating adenosine receptors) .
11) Valerian Root May Improve OCD
An 8-week pilot (RCT) of 31 adults with OCD found that valerian reduced OCD symptoms compared to placebo .
12) Valerian Root May Prevent Dizziness
The drug efavirenz used in HIV patients is known to cause dizziness (vertigo). In a 4-week pilot study of 51 HIV positive patients, the frequency of dizziness was lower in the valerian treated group than the placebo group .
13) Valerian Root May Relieve Digestive Problems
Valerian is used as a home remedy for stomach cramps. Although current evidence does not support the use of valerian as a digestive aid, it can reduce muscle spasms (antispasmodic) .
A study using guinea pigs showed that valepotriates and the essential oil present in valerian reduced contractions in the small intestine .
14) Valerian Root May Improve Memory and Cognitive Function
Older people are more vulnerable to memory loss and other types of cognitive impairments after surgery. A (DB-RCT) study of 61 patients between 30 and 70 years of age found that valerian reduced the risk of cognitive decline a month after heart surgery compared to placebo .
15) Valerian Root May Improve Fibromyalgia
Bathing in a valerian bath 3 times a week for 3 weeks significantly improved well being and sleep and decreased pain (tender point count) in 30 people with fibromyalgia .
16) Valerian Root May Prevent Kidney Damage
In rats with high cholesterol levels, valerian protected against kidney damage caused by a high amount of fats in the diet .
17) Valerian Root May Increase Dreaming
Drugs that affect the GABA system, like valerian, are linked to patient reports of vivid dreams .
However, another sleep study of 128 people found no increase in dream recall with valerian .
Although there is popular opinion supporting the use of valerian for these conditions, there is no scientific evidence backing its use in:
- Shin Splints: Valerian is used as a home remedy for shin splints (medial tibial stress syndrome). Anecdotal evidence suggests that drinking valerian tea relaxes the muscles and reduces pain .
- Migraines and Headaches: Despite its traditional use, the evidence is lacking for valerian reducing the severity of migraines and headaches .
- Joint Pain in Arthritis: Despite the historical use of valerian to relieve joint pain, there are no studies to support this. Anecdotal reports of its effectiveness may be due to its general calming effects .
- Knee Pain: People with knee pain report some relief with valerian. Valerian may also be useful as a mild sleep aid in people with rheumatoid arthritis .
- Sciatica Pain: People with sciatica taking valerian report some pain relief. This may be due to its muscle relaxant effects .
- Hand Tremors: Valerian may reduce hand tremors through its anti-anxiety effects. However, the evidence is anecdotal .
- Heart Palpitations: Valerian is traditionally known to decrease heart palpitations. It may do this by its relaxing effects on smooth muscle [R, 102].
- Depression in Bipolar Disorder: The sedative effects of valerian may improve depression in bipolar disorder. However, there is no clinical evidence available to support this, although valerian did improve depression in rats .
Valerian Root Risks and Side Effects
Valerian is commonly reported to have no side effects. However, clinical studies show that it can, in fact, cause side effects. Long-term safety data are not available .
Valerian has been classified as “generally recognized as safe” in the U.S. .
Although not all side effects are known, valerian is thought to be safe when taken for a short period of time (4 to 8 weeks) by healthy adults at recommended doses .
- Upset stomach
- Dry mouth
- Thinking problems
- Strange dreams
- Heart palpitations
- Feeling excited or uneasy, especially at high doses
- Liver toxicity (hepatotoxicity) with long-term use at high doses
- Addiction is occasionally reported with withdrawal effects on sudden cessation
Can Valerian Root Be Harmful?
- Allergic Reaction: People with allergies to plants in the Valerianaceae family may be allergic to valerian. An occasional allergic reaction is reported (anecdotal) with side effects including breathing problems or chest tightness, chest pain, skin hives, rash, or itchy or swollen skin .
- Addiction: Medical reports link overuse of valerian to liver toxicity and addictiveness [114, 115].
- Drowsiness: At high doses, daytime drowsiness can occur and caution is advised while driving or operating machinery [113, 116, 117].
- Increased Effects of Anesthetics: If you need surgery, stop taking valerian at least 2 weeks ahead of time. Valerian may increase the effects of anesthetics that act on GABA receptors .
- Withdrawal Symptoms: Heart problems and delirium may occur if valerian is stopped suddenly .
- Toxic to Cells (cytotoxic): Valepotriates in valerian caused changes to DNA (mutagenic) in laboratory studies, but were not cancer-causing in animal studies [106, 118, 115, 119, 120].
- Overstimulation: At high doses, excitation may occur in some people .
- Suicide: Researchers report 1 case of attempted suicide after taking a massive overdose of valerian .
Limitations and Caveats
Valerian illustrates both the negative and positive aspects of herbal drugs. The variability in its composition and the instability of some of its chemicals make standardization difficult .
The composition of any valerian product may vary considerably between manufacturing lots, as dietary supplements are not always tested for consistency and seasonal variations in valerian’s many active compounds are known .
Animal studies and anecdotal reports suggest that valerian may increase the action and side effects, including the amount of drowsiness, caused by sedative drugs.
- Benzodiazepines, such as lorazepam (Ativan)
- Barbiturates, such as phenobarbital
- Narcotics, such as codeine
- Antidepressants, such as fluoxetine (Prozac)
- Antihistamines, such as diphenhydramine (Benadryl)
- Some anti-seizure or antidiarrheal drugs
However, there is little evidence for clinically relevant interactions in humans .
Natural Sources (or Forms of Supplementation)
Even in standardized plant extracts, there is some variation in the number of different chemicals, which may account for different reports of efficiency. However, the clinical effects are remarkably consistent across different preparations .
The content of volatile oils and the plant’s clinical effects show little correlation .
However, the content of volatile oils (valerenic acids, sesquiterpenes, valepotriates) is sometimes used to standardize valerian extracts. Valerian is sometimes combined with other herbs such as lemon balm, passion flower, and hops [59,].
Valerian root can be purchased as a supplement in a variety of forms online or at your local health food store.
Recommended doses range from 400 mg to 900 mg at bedtime .
Valerian is most effective if taken regularly for 2 or more weeks. It may take a few weeks before the effects of valerian root supplementation are felt .
Higher dosages may have a stimulating effect, so it is best to start with a minimal dose and use the lowest dose needed to achieve the desired effect .
Valerenic acid levels are measurable for at least 5 hours after taking valerian. The average elimination half-life for valerenic acid is 1.1 hrs .
Valerian Root Response May be Affected by Genetics
There are specific binding sites on GABA A receptors for the compounds valerenic acid and valerenol (found in valerian). A genetic mutation in mice significantly reduces the response to valerian [102, 133].
Valerian root is often combined with other sedating herbs, such as hops (Humulus lupulus), St. John’s Wort, kava, and lemon balm (Melissa officinalis) to treat insomnia.
“…when I drink a valerian tea before going to sleep when I wake up in the morning, I feel like I had a heavy sleep but a good one, you know, like the nights you got in holidays when all your stress goes away and you sleep like a baby.”
“VR half an hour before bed works for me. I also give it to my daughter when she is having difficulty sleeping and it works for her too. No bad effects for any of us. Recommend taking 2 capsules half an hour before going to bed. You will get a good night’s sleep”
“I work nights and from time to time have difficulty staying asleep once I fall asleep. Taking valerian root has really helped with that problem. I started taking valerian when I was traveling a lot to help prevent jet lag and it really helped with that problem as well.”
“I take 3 to 4 valerian root capsules as a sleep aid. I also find myself dreaming more, or at least remembering more dreams.”
“Helps me more compared to Lexapro, Celexa, Xanax, Vistaril, etc. without negative side effects. Only side effect experienced is tiredness, which is manageable compared to suicidal tendencies caused by other medications.”
“When I am feeling anxious or nervous, I take one capsule and it helps to take the edge off my nervousness without making me drowsy. I have had no side effects from the drug.”
“I am on my second bottle of dried valerian root extract (very concentrated) and I use an alcohol-free tincture. I have been using it over a month. It is very effective, I use it primarily to calm anxiety and drink 30 drops diluted into a beverage a couple times during the day. I am a very manic person and if I drink enough, it can make me sleepy, but usually, I just find it calming and use it during the daytime as well as before bed to sleep better.”
“I was recently diagnosed with fibromyalgia. I actually could feel my entire body relax. I’ve just finished my Extra Sleepy Time Tea – I used 4 bags for 100 mg. The first time I did this I woke up feeling well rested and refreshed. I can’t remember the last time I woke up feeling “good” vs. my joints cracking and moaning when I first get moving!”
“It works! It also seems to help reduce my hot flashes due to menopause.”
“I have been having a hard time getting to sleep (hot flashes, anxiety, etc.). I am so happy that I found valerian. Not only has it made me sleep well, but it is also helping with my anxiety and ADD… an added effect I did not know would happen. I am so happy!”
“Valerian root has been very beneficial for symptoms of my Asperger’s syndrome. Anxiety in social situations and overstimulation cause inability to sleep well and that will cause problems at school and work. I started taking 2 of the 450 mg Valerian root every night after a week I noticed I could function better during the day and less anxious in a college setting. Warning, do not drink alcohol before bedtime when taking valerian. They don’t mix.”
“This is the best thing for my epilepsy. I am on prescribed Keppra that makes me feel high as a junky on Ecstasy. Epilepsy Foundation needs to help us all become less dependent on corp. pharm. and endorse this along with cannabis, marijuana.”
Valerian Root vs. Melatonin
Both valerian and melatonin are sleep aids, although their mechanisms are different.
Sometimes they are combined together but caution should be exercised, as the sedative effect may be too high .
Studies have shown lower doses of melatonin are more effective in promoting sleep .
As with valerian, too high a dose can have the reverse effect, making it more difficult to fall and stay asleep. Even melatonin is only a short-term solution as it loses effectiveness with long-term use .