Valerian: recommended daily dose and upper limit

There is no officially recommended daily dose and no established upper limit for valerian. In clinical trials, the doses tested vary widely (for example, 300 mg and 600 mg in a trial in adults with disturbed sleep), taken in the evening, but the results have been inconsistent and the preparations vary widely between studies. This means that any number you see — 300, 600 or 900 mg — is a research reference, not an instruction for use.

If you are thinking of trying valerian, the most sensible approach is to follow the dose given on the label of the product you choose, start with the lowest one and not increase it on your own. Below we explain what the studies actually tested, why milligrams are not comparable between forms of valerian and what you need to know about safety and interactions.

What doses of valerian have been studied?

The numbers vary quite a lot, and it is important to look at the type of study and the population before drawing conclusions.

• 300 mg and 600 mg of a standardised extract (Li 156), in a single dose at 21:00, were compared with placebo in 16 adults with disturbed sleep, aged 50 to 64, in a crossover trial with sleep EEG. No significant differences were observed in any sleep parameter or in the psychometric tests the following morning.
• 450 mg and 900 mg of aqueous extract were tested in healthy young people: at home, both doses reduced perceived sleep latency and time awake after falling asleep, with a suggestion of a dose-dependent effect; in the sleep laboratory, with only the higher dose, there were no significant differences compared with placebo.
• 600 mg of extract (Li 156) in the evening, for 14 days, did not impair reaction, concentration or coordination in 91 volunteers analysed, in a double-blind trial.
• 900 mg of extract (0.8% valerenic acid), as a single dose, was used in a crossover trial with 15 healthy volunteers to assess cortical excitability by transcranial magnetic stimulation.
• 1600 mg in a single dose was tested in a placebo-controlled crossover trial to assess subjective sleepiness, sobriety tests and performance in a driving simulator; there were no significant differences in reaction times or in the sleepiness scales, but the authors note that the study may have had insufficient statistical power.

Note that these doses refer to specific, often standardised extracts, and not to powdered root. A meta-analysis of 16 trials with 1093 participants found, in 6 studies that reported sleep quality as a dichotomous outcome, a statistically significant benefit in self-reported sleep quality, but with evidence of publication bias and great heterogeneity of doses and preparations. A more recent systematic review, which analysed 14 trials with 1602 participants with insomnia, found no significant differences between any medicinal plant — including valerian — and placebo or active control in any of the 13 clinical efficacy measures.

Why milligrams are not all equal

"Valerian" can mean very different things: dried powdered root, standardised dry extract, fluid extract or tincture. Each form has different concentrations of compounds such as valerenic acid, and 300 mg of one does not equal 300 mg of another. A review of 60 studies (n=6894) suggested that the inconsistency of the results may be due precisely to the variable quality of the extracts, and that more reliable effects could be expected from the whole root/rhizome.

That is also why it makes no sense to directly compare the dose from one study with that of a different product. What matters is the amount of standardised extract per serving and the percentage of active compounds stated on the label.

Is there an official upper limit?

No. Neither EFSA nor other regulatory bodies have established a maximum daily dose for valerian. What exists is safety data from clinical trials: in a review of 60 studies, no serious adverse events associated with taking valerian were reported in participants aged between 7 and 80 years. This is not the same as saying that any dose is safe, especially in the long term or in specific populations.

A meta-analysis of 14 trials in people with insomnia noted that, compared with placebo, a greater number of adverse events per person was reported with valerian, unlike other plants such as kava, chamomile and wuling. The effects most frequently described in the literature include headaches, dizziness and gastrointestinal discomfort. High doses may increase drowsiness, which is relevant for those who drive or operate machinery — although, in the trial with 1600 mg as a single dose, no significant differences were observed in the sobriety tests and the driving simulator.

In addition, valerian may potentiate the effects of other plants with a sedative action, such as chamomile, so you should not add valerian to other sleep supplements without talking to a healthcare professional. Some people also report nightmares or paradoxical agitation — instead of drowsiness, they feel more active. If that happens, stop and talk to a pharmacist.

Valerian and sleep: what the evidence allows us to say

Valerian has been used for centuries as a sleep aid, but the modern evidence is mixed. An umbrella review from 2024, which gathered systematic reviews on the subject, concluded that the data suggest a good safety profile but showed no evidence of efficacy in the treatment of insomnia; valerian appeared effective only in the subjective improvement of sleep quality, without confirmation in quantitative or objective measures.

This does not mean it cannot help some people fall asleep more easily. It means there are no guarantees, that part of the effect may be attributed to the context of taking it and that individual response varies. If you decide to try it, give it at least one to two weeks before assessing it and do not increase the dose if you notice no difference.

To better understand what is known about the mechanism of action, see the article on how valerian works.

How to compare the study dose with the label dose

The practical rule is simple: look on the label for the amount of extract per serving and the standardisation (for example, "extract standardised to 0.8% valerenic acid"). Only then compare it with what the studies used — and remember that study doses are not instructions for use.

If your product states, for example, 300 mg of extract per serving, it is within the most common range in trials — but that is not a recommendation to take it nor a guarantee of effect. Always follow the manufacturer's instructions.

How long to take it and when to stop

Clinical trials vary greatly in duration: from a single dose to 14 days or five nights. There are no data establishing an ideal period of use or a schedule of breaks. If you feel you need to take valerian every night for several weeks, it is a sign that you should talk to a healthcare professional about the cause of the problem.

There is no solid evidence on an ideal schedule of breaks, but some experts recommend periodically interrupting prolonged use. Continued use for months without supervision is not advisable, and if you feel you need valerian every night for several weeks, talk to your doctor.

If after two weeks you notice no difference, increasing the dose is not the most likely answer. It is worth more to review your sleep hygiene and seek help if the insomnia persists.

If valerian is not helping, first review your sleep hygiene: regular schedules, avoiding screens before bed, reducing caffeine and creating a dark and quiet environment. Often these are the factors that influence sleep the most. If the insomnia persists, consult a doctor — it may be a symptom of other health problems, such as anxiety, depression, sleep apnoea or restless legs syndrome.

Safety, interactions and who should take care

Valerian may potentiate the effects of sedatives, anxiolytics, antidepressants and antihistamines, and should not be combined with alcohol. If you take any of these medicines, talk to your doctor or pharmacist before starting. The same applies to those with liver disease.

At high doses, valerian may cause daytime drowsiness, which is relevant for those who drive or operate machinery. The side effects most frequently described include headaches, dizziness, itching and gastrointestinal discomfort.

Pregnant women, breastfeeding women and children should not take valerian without professional advice. To explore this topic further, see the articles on drug interactions, effects and precautions and valerian in pregnancy.

If you are thinking of an alternative without valerian, Valerian Gummies are not part of our range; you can explore the Sleep and Relaxation collection to see the options available. If in doubt about which to choose, talk to a pharmacist.

If valerian is not enough

Persistent insomnia may have causes that a supplement does not resolve: anxiety, depression, sleep apnoea or restless legs syndrome, among others. In those cases, the right step is to seek medical assessment. Cognitive behavioural therapy for insomnia is considered the first-line treatment and does not depend on supplements.

If you are looking for alternatives in our range, you can explore the Sleep and Relaxation collection or the valerian ingredient page for more context. To find out when to take it, see valerian: when to take it.