Educational information, not medical advice — ask your doctor or midwife.
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 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.
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.
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.
Stop and get urgent medical care if you notice yellow skin or eyes, dark urine, pain in the upper right belly, or deep tiredness. These can be signs of liver trouble.
Stop and see your doctor if you feel very sleepy in the daytime. Do the same if you feel oddly restless or wound up.
See your doctor if your sleep is no better after two to four weeks. Poor sleep can be a sign of depression, pain, thyroid problems or sleep apnoea (breathing pauses during sleep).
In the UK and EU, valerian is licensed as a traditional herbal medicine for mild sleep problems and tension. In the US it is sold as a dietary supplement and is not approved as a drug.
Evidence grades and traditional-use labels are explained in our methodology. Nothing here is medical advice.
What it is typically used for, usual dose, cautions, and the study behind it where real trial data exists.
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