Valerian
Valerian is a plant native to Europe and Asia; it also grows in North America. The evidence on whether it helps with sleep problems is inconsistent, and the American Academy of Sleep Medicine recommends against it for chronic insomnia. There is not enough evidence to say whether it is useful for any health condition.
Valerian is a plant native to Europe and Asia; it also grows in North America.
Research & evidence
Strong support Some support Weak or no supportColours show how well the sources back each point. The reason is next to each one.
A relatively small amount of research has looked at valerian, and there is not enough evidence to determine whether it is useful for any health conditions.
Limited evidenceSome support. Not enough good evidence to say
Study details
NCCIH: "There is not enough evidence to determine whether valerian is useful for any health conditions."
Source: NCCIH, Valerian (Last Updated May 2025), What Have We Learned? View source
The evidence on whether valerian helps sleep problems is inconsistent, and in its 2017 guidelines the American Academy of Sleep Medicine recommended against using valerian for chronic insomnia in adults.
Mixed evidenceSome support. Results are mixed
Study details
NCCIH: "The evidence on whether valerian is helpful for sleep problems is inconsistent."
Source: NCCIH, Valerian (Last Updated May 2025), What Have We Learned? View source
NIH ODS says the nine studies its cited review covered were not sufficient to determine whether valerian works for sleep disorders, and that one trial couldn't show clinical significance for insomnia because participants didn't need to have insomnia.
Limited evidenceSome support. Not enough good evidence to say
Study details
ODS: "not sufficient for determining the effectiveness of valerian to treat sleep disorders." ODS: "The clinical significance of the use of valerian for insomnia cannot be determined from the results of this study."
Source: NIH ODS, Valerian Health Professional Fact Sheet (Updated March 15, 2013), Research findings (systematic review); NIH ODS, Valerian Health Professional Fact Sheet (Updated March 15, 2013), Research findings (first trial) View source
Dosage
| Form | Amount |
|---|---|
| Any form | No standard dose is listed by our sources. NCCIH says valerian has been used with apparent safety in adults at 300 to 600 milligrams a day for up to 6 weeks; the safety of long-term use is unknown. |
Side effects
Side effects include headache, stomach upset, mental dullness, excitability, uneasiness and vivid dreams. In very rare cases, liver injury was reported, most often in combination with other herbals. Don't take it with alcohol or sedatives, and don't drive after taking it.
Well documented Reported (case reports, anecdotal or one study) None reportedThe circle shows how well documented an effect is, not how serious it is. A rarely reported effect can still be serious, so always read ‘When to stop’.
| Effect | Frequency | When to stop |
|---|---|---|
| Headache, stomach upset, mental dullness, excitability, uneasiness, vivid dreamsReportedDescribed as anecdotal by NIH or MSK | Not stated; MSK calls most effects occasional or anecdotal, and mostly mild to moderate | Stop and talk to a doctor if it persists. Don't drive if you feel dull or drowsy. |
| Withdrawal symptoms (anxiety, irritability, heart disturbances, insomnia, and in rare cases hallucinations) if stopped abruptly after long-term useReportedDescribed as anecdotal by NIH or MSK | Some people (NCCIH) | If you've taken it long term, talk to a doctor before stopping. |
| Liver injury; liver and pancreatic toxicities have also been reportedReportedCase reports only | Very rare for liver injury (NCCIH); case reports (MSK) | Stop and get medical help right away. |
Safety & interactions
Safety
NCCIH says research suggests valerian is generally safe for short-term use by most adults; it has been used with apparent safety at 300 to 600 mg a day for up to 6 weeks, but the safety of long-term use is unknown. NIH ODS says few adverse events attributable to valerian have been reported for clinical study participants. NCCIH says that in very rare cases, liver injury was reported when taking valerian, most often in combination with other herbals, and its long-term effect on the liver is unknown. MSK says that although valerian products are generally safe, liver and pancreatic toxicities have been reported. If you take any type of medicine, talk with your health care provider before using valerian or other herbal products.
Contraindications
MSK says people with liver or pancreatic disease should avoid valerian because of case reports of liver toxicity and a possible link with acute pancreatitis. MSK also says not to drive or operate dangerous machinery after taking valerian, because it could disrupt information processing, task performance and alertness. MSK says pregnant or nursing women should avoid valerian, as it has not been adequately studied and animal studies suggest some harm to fetal brain development; NIH ODS says women who are pregnant or nursing should not take valerian without medical advice. NCCIH says it should not be taken along with alcohol or sedatives. MSK says valerian should be stopped at least 1 week before surgery because it may interact with anesthesia.
Drug interactions
NCCIH says valerian should not be taken along with alcohol or sedatives. NIH ODS describes a theoretical possibility of additive sedative effects from alcohol or sedative drugs.
MSK reports that in animal models, valerian prolonged pentobarbital-induced sleep.
MSK says an animal study and case report suggest valerian may have synergistic effects.
MSK says an animal study suggests valerian may have an additive effect, causing hepatic damage.
MSK says valerian may inhibit CYP2D6, though other studies, including in people, suggest these interactions are unlikely.
MSK says valerian may inhibit CYP3A4, though other studies, including in people, suggest these interactions are unlikely.
MSK says valerian may inhibit P-gp transporters and affect the concentration of the drugs they carry, though another study suggests this is less likely in the body.
MSK says preclinical studies suggest valerian affects UGT enzymes and may increase the side effects of drugs they process; clinical relevance hasn't been determined.
MSK says valerian should be discontinued at least 1 week before surgery because it may interact with anesthesia.
Established: stated plainly by an authoritative source. Documented: supported by case reports or trial data. Theoretical: based on mechanism, animal data, or a cautious listing. Always check with your pharmacist or prescriber.