Valerian Root for Sleep: Benefits, Side Effects and Cautions

Quick answer

Valerian root has been used as a sleep aid since ancient Greece and is still one of the best-selling herbal sleep supplements. Research results are inconsistent: some studies found people felt they slept better, but when sleep was measured objectively in a sleep lab, valerian usually made little difference. The US National Center for Complementary and Integrative Health describes the evidence as inconclusive.

Valerian is generally safe for short-term use in healthy adults, but it can cause headaches, dizziness and morning grogginess, and it should not be combined with alcohol or other sedatives.

What valerian is

Valerian (Valeriana officinalis) is a flowering plant whose roots have a strong, earthy smell that many people find unpleasant. The root contains valerenic acid, valepotriates and other compounds that may increase the activity of GABA, the brain's main calming messenger. Products vary widely in how they are made and how much of these compounds they contain, which is one reason studies disagree.

What the research says

• A 2006 meta-analysis in the American Journal of Medicine found that valerian might improve sleep quality, but noted significant evidence of publication bias (positive studies being more likely to be published).
• A 2010 meta-analysis in Sleep Medicine found that people taking valerian reported better sleep quality, but objective measures of sleep, such as time to fall asleep and total sleep time, did not improve significantly.
• Some studies suggest valerian needs to be taken nightly for two to four weeks before any effect appears, rather than working on the first night like a sleeping pill.
• Studies combining valerian with hops or lemon balm have shown some benefit, but it's hard to know which ingredient is responsible.

Overall, valerian may help some people feel they sleep better, but it is not a reliable treatment for insomnia.

How people use it

• Typical doses in studies: 300 to 600 mg of valerian root extract, taken 30 minutes to 2 hours before bed. Follow the product label.
• Valerian tea: 2 to 3 grams of dried root steeped in hot water for 10 to 15 minutes. The taste is strong and earthy.
• Give it time: if you try it, take it nightly for 2 to 4 weeks before deciding whether it helps.
• Short-term only: most studies lasted 4 to 6 weeks. Long-term safety is not well established.
• Choose a quality product: look for products tested by independent organisations, because content varies.

Possible side effects and interactions

Valerian is usually well tolerated in short-term use. Possible side effects include:

• Headache, dizziness
• Stomach upset
• Morning drowsiness or feeling "hungover"
• Vivid dreams
• Paradoxically, some people feel restless or have trouble sleeping

Rare cases of liver injury have been reported, mostly with multi-herb products, so a direct link is uncertain.

Withdrawal-like symptoms (such as anxiety and a racing heart) have been reported in a person who stopped very high doses suddenly after long-term use. If you have taken valerian for a long time, reduce it gradually.

Interactions:

• Alcohol, benzodiazepines, sleeping tablets, opioids, antihistamines and other sedatives: increased drowsiness
• Anaesthesia: stop valerian about two weeks before surgery, and tell your anaesthetist
• Medicines processed by the liver: valerian may affect some liver enzymes, although studies suggest this effect is small

Who should avoid it

• Pregnant or breastfeeding women, as safety hasn't been established
• Children under 3; older children only on medical advice
• People with liver disease
• People taking sedating medicines or who drink alcohol regularly in the evening
• People with upcoming surgery

When to see a doctor

See a doctor if:

• You have had difficulty sleeping at least three nights a week for three months or more
• You feel very sleepy during the day, or have fallen asleep while driving
• You snore loudly, gasp or stop breathing during sleep (possible sleep apnoea)
• You have restless legs, pain, frequent urination at night or breathing problems keeping you awake
• Your sleep problems come with low mood, anxiety or other mental health concerns

The best-supported long-term treatment for chronic insomnia is cognitive behavioural therapy for insomnia (CBT-I), which is available through doctors, psychologists and some digital programmes.

Frequently asked questions

Is valerian addictive?

It does not appear to cause dependence like some sleeping pills, but stopping high doses suddenly after long-term use may cause withdrawal symptoms in rare cases. Reduce gradually.

Can I take valerian with melatonin?

Some products combine them. There is no strong evidence the combination works better, and combining sedating products increases the risk of next-day drowsiness. Check with a pharmacist.

Why does valerian smell so bad?

The smell comes from isovaleric acid, which forms as the root dries. Capsules avoid the taste.

How quickly does valerian work?

Some people notice a difference within days, but studies suggest it may take 2 to 4 weeks of nightly use.

References

• National Center for Complementary and Integrative Health (NCCIH). Valerian. https://www.nccih.nih.gov/health/valerian
• NIH Office of Dietary Supplements. Valerian: fact sheet for health professionals. https://ods.od.nih.gov/factsheets/Valerian-HealthProfessional/
• Bent S, et al. Valerian for sleep: a systematic review and meta-analysis. American Journal of Medicine, 2006.
• Fernández-San-Martín MI, et al. Effectiveness of valerian on insomnia: a meta-analysis of randomized placebo-controlled trials. Sleep Medicine, 2010.