The short answer
Have valerian reviewed before taking it with phenobarbital. Guidance advises against combining valerian with sedatives, although the exact combination has not been tested adequately.
What this answer covers
Oral Valeriana officinalis preparations; not another Valeriana species or an unidentified root mixture.
- Supplement or preparation
- Valeriana officinalis
- Medication ingredient
- phenobarbital
Why there is a precaution
Valerian may cause mental dullness and might have sleep-inducing effects. NCCIH advises against taking it with sedatives. This supports caution without claiming a known rate of harm for this exact pair.
A negative sleep study is not a safety clearance
A controlled study did not find its valerian preparation better than placebo on the primary insomnia outcome. It did not study this medication combination or show that all valerian products are free of sedating effects.
Plan changes rather than spacing doses
No protective interval is established. Tell the clinician about regular valerian use; abrupt stopping after chronic use has sometimes been followed by withdrawal symptoms.
Watch for impaired alertness
Phenobarbital can cause drowsiness and impaired coordination. Avoid driving when affected, and seek urgent help for severe difficulty waking or breathing. Other sedating medicines and alcohol make a careful medication review especially important.
Evidence and practical considerations
Side effects & toxicity
Conditional co-use avoidance/review rests on exact medication CNS effects and species-specific valerian guidance; no established spacing solution.
- Exact scope
- Oral Valeriana officinalis preparations; not another Valeriana species or an unidentified root mixture. with Exact oral phenobarbital; parent and metabolites distinguished; no other drug/route assumed equivalent.
- Medication form and route
- oral supplement unless pregnancy section explicitly distinguishes neonatal injection
- Timing or duration
- Preparation, dose and duration determine applicability; chronic nutrition evidence is not a single-dose interaction.
What remains uncertain
- No exact combination trial; uncertain sleep benefit does not prove absence of additive impairment.
Factors that may matter: exact supplement identity; dose; other medicines; clinical indication; baseline nutrition; pregnancy where relevant.
Read the supporting source summaries
Source 1: current product label
dailymed.nlm.nih.gov · Source check Sep 10, 2026
Population: People prescribed oral phenobarbital.
Causes CNS depression and can impair driving; other CNS depressants can add to these effects. Adult plasma half-life is prolonged. Abrupt withdrawal after dependence can cause seizures and other serious symptoms. Long-term treatment warrants periodic clinical and laboratory assessment.
How this applies: Exact RxCUI 8134 IN and UNII YQE403BP4D, oral plain ingredient; no automatic sodium-injection or other barbiturate transfer.
Does not name the requested botanicals or establish supplement-specific interaction rates or spacing. Current DailyMed listing is unapproved drug other, not evidence of FDA approval.
Source 2: official guidance
nccih.nih.gov · Source check Sep 10, 2026
Population: People considering the specified supplement.
Possible but unproven sleep-inducing effect; advises against use with alcohol or sedatives. Mental dullness can occur; long-term safety is uncertain.
How this applies: Preparation-specific context; not a directly measured either requested antiseizure drug interaction.
No either requested antiseizure drug interaction trial. Chronic use can be followed by withdrawal symptoms when stopped abruptly.
Source 3: randomized placebo-controlled trial
pubmed.ncbi.nlm.nih.gov · Source check Sep 10, 2026
Population: 391 adults randomized to three groups in an internet-based trial.
Neither active intervention improved its primary anxiety or insomnia outcome more than placebo.
How this applies: Preparation-specific context; not a directly measured either requested antiseizure drug interaction.
Not both active botanicals together, not either requested antiseizure drug co-use. Accessible abstract does not fully characterize dose and preparation; efficacy result is not proof of combination safety.
Research assessment: · Open full citations ↗
Review and change history
- Publication status
- Published research summary
- Clinical review
- Not yet recorded
| Date | Update |
|---|---|
| Article prepared | |
| Exact current available claims reviewed against captured originals; no clinical review asserted. | |
| Research summary published |
Article revision: 8b4298ab774a9dcf
This guide brings together the evidence records used by our interaction checker. Each finding retains its own preparation limits, research date, and source summaries.
Full citations require verification. Reading this answer and the source summaries does not.
Taking other supplements or medications?
Use the checker to explore your other combinations. Ask a pharmacist to review the exact products, amounts and medical conditions in your complete list.
Open the interaction checkerInformation, not medical advice. Do not change prescribed treatment based on this guide.