What is Valerian?

Valerian is a herbal sleep aid made from the root of a tall European plant. In German it is known as Baldrian. The dried root has a strong, musty smell.

People take it for trouble sleeping and for feeling wound up. It is sold as capsules, tablets, drops and tea. It is often mixed with hops or lemon balm.

The evidence is mixed. Some trials show a small gain in how well people say they slept. Many careful trials show no clear gain over a dummy pill.

Long use in folk medicine is not proof that it works. It is also not proof that it is safe.

How does Valerian work?

How valerian works is not settled. Lab work gives clues, but the human picture is still thin.

In cell studies, a compound called valerenic acid appears to act on GABA receptors. GABA is the brain's main calming signal. Drugs that boost GABA can make people sleepy.

Whether valerian does the same in the human brain is not proven. The amount that reaches the brain after a capsule may be small.

The root also holds a little GABA itself. Most researchers doubt that this gets from the gut to the brain. In cell tests, other parts of the root may touch serotonin and adenosine signals, which are also tied to mood and sleep.

What forms does Valerian come in?

Valerian is sold in several forms. The most common are: - Capsules and tablets of dried root extract - Liquid drops, or tincture in alcohol - Tea bags and loose dried root - Mixed sleep products with hops, lemon balm or passionflower - Bath products and drops aimed at children

Tea tastes and smells strong, and many people dislike it. Alcohol-based drops do not suit everyone. Mixed products make it hard to tell which herb caused any effect, good or bad.

Where it comes from:

Valerian has a long written record in Europe. Greek and Roman writers described the root as a medicine. Later it became known across German-speaking Europe as Baldrian.

Folk healers gave it for 'nerves', restlessness, cramps and bad sleep. A bedtime tea of the root was a common home remedy.

Reports from the First World War describe it being given to soldiers for shell shock. It stayed in German and British herbal books into modern times.

What does Valerian help with?

• Trouble falling asleep: This is the main modern use, and the evidence is mixed. Older pooled reviews found people said they slept better. Those studies were small and poorly run. Better-run trials since then found little or no gain over a dummy pill. Sleep lab readings, such as time taken to fall asleep, often did not improve.
• Poor sleep quality: Some people report calmer, deeper sleep after a few weeks. This shows up in self-rated scores more than in lab measures. The effect, where it is seen, is small. It is not on the level of a prescription sleep drug.
• Nervous restlessness and mild tension: European folk use was for 'nerves' and daytime unease. Modern trials are few and small. Results are weak and not consistent. Valerian is not a treatment for an anxiety disorder, and it should not replace care your doctor has set up.
• Period cramps: Tradition used the root for cramping pain. A few small trials in students suggest less pain, but the studies are low quality. This is not settled. Treat any claim here as unproven.
• Hot flushes around menopause: A small number of trials report fewer or milder hot flushes. The trials are short and small. The findings have not been firmly repeated. Evidence here is thin.
• Restless legs: One small trial reported less daytime sleepiness in people with restless legs. Leg symptoms themselves changed little. One small study is not enough to rely on.

What are the side effects of Valerian?

• Morning grogginess or daytime sleepiness
• Headache
• Dizziness
• Upset stomach or loose stools
• Dry mouth
• Vivid or odd dreams
• Feeling restless or wound up instead of calm (uncommon)
• Rare reports of liver problems, mostly with mixed-herb products

Good to know:

Most side effects are mild and pass. In trials, rates were close to those seen with a dummy pill.

The main day-to-day risk is drowsiness. That matters if you drive, use machines or care for a child at night.

Liver reports are rare and most involved products with several herbs. Stop and seek care at once if you notice yellow skin or eyes.

How much Valerian should you take?

• Recommended daily: These are label figures, not advice for you. Ask a pharmacist or doctor what suits your case. Packs in Europe and the US commonly carry 300 mg to 600 mg of dried root extract per evening dose. Tea packs often use about 2 to 3 grams of dried root per cup. Strength varies a lot between brands. Do not assume two packs with the same number are the same.
• Best time of day: Most people take it in the evening, about 30 minutes to two hours before bed. Some products are taken two or three times a day for daytime tension. Daytime doses can leave you drowsy. Do not drive until you know how it affects you.
• With or without food: Either way works. A little food may ease stomach upset. Do not take it with an alcoholic drink. Alcohol adds to the sleepy effect.
• Time to effect: Some people feel calm or sleepy the first night. Others feel nothing at all. In trials, any benefit often needed two to four weeks of nightly use. It is honest to say it may do nothing for you.
• How long to take it: Valerian is normally used short term. European product guides suggest a review after two to four weeks. Long-term daily use has not been well studied. A few case reports describe shaky, anxious feelings after stopping long daily use. If your sleep is no better after a month, see your doctor rather than taking more.