The short answer
Identify the valerian species before using this root product with lorazepam. Its inventory name alone does not establish which evidence applies.
What this answer covers
Radix et Rhizoma Valerianae has unresolved species identity; Valeriana officinalis evidence applies only after a match is confirmed.
- Supplement or preparation
- Radix et Rhizoma Valerianae
- Medication ingredient
- lorazepam
Start with the botanical identity
Ask the pharmacist to confirm the Latin species, root or rhizome, extraction method and other ingredients. Do not assume the inventory name means Valeriana officinalis.
What the guidance supports
NCCIH advises against Valeriana officinalis with sedatives because sleep-inducing effects are possible. This precaution depends on identifying the actual product.
The reported combination used two identified herbs
A lorazepam case involved both Valeriana officinalis and passionflower, with dizziness, shaking and fatigue. It cannot identify the species in your root product or isolate valerian as the cause.
Watch for impaired alertness
Lorazepam can affect alertness and coordination. Avoid driving if affected. Seek urgent help for severe difficulty waking or breathing, and tell the prescriber about alcohol, opioids and all other sedating products.
Evidence and practical considerations
Side effects & toxicity
Identity-specific review and conditional alertness precaution are appropriate; exact-pair risk magnitude remains unmeasured.
- Exact scope
- Radix et Rhizoma Valerianae has unresolved species identity; Valeriana officinalis evidence applies only after a match is confirmed. with Exact oral lorazepam tablets. Rapid conjugation to lorazepam glucuronide, which has no demonstrable CNS activity in animals. Oral tablet scope; injected lorazepam is not assigned the same supplement evidence.
- Medication form and route
- oral
- Timing or duration
- Source-specific single-dose, repeated-dose and observational exposures distinguished.
What remains uncertain
- Unknown root species cannot be assigned V. officinalis evidence. The lorazepam case also included passionflower, leaving causality and extract-specific risk uncertain.
Factors that may matter: preparation and plant part; clinical indication; dose; other medicines; baseline alertness.
Read the supporting source summaries
Source 1: current product label
dailymed.nlm.nih.gov · Source check Sep 10, 2026
Population: Patients prescribed oral lorazepam.
Can impair alertness and coordination; other CNS depressants can increase impairment. Opioid combinations have a specific respiratory-depression warning. Dependence and withdrawal require supervised changes. Rapid conjugation to lorazepam glucuronide, which has no demonstrable CNS activity in animals. Oral tablet scope; injected lorazepam is not assigned the same supplement evidence.
How this applies: Exact IN and labeled oral formulation; route, salt and metabolite distinctions retained.
No quantified risk for every herb or universal protective spacing interval. Opioid-specific evidence does not prove equal botanical respiratory risk.
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 lorazepam interaction.
No lorazepam interaction trial. Chronic use can be followed by withdrawal symptoms when stopped abruptly.
Source 3: original human study
pubmed.ncbi.nlm.nih.gov · Source check Sep 10, 2026
Population: Twelve healthy volunteers.
Alprazolam peak concentration increased modestly, but AUC and elimination half-life did not change significantly.
How this applies: Original named medication and preparation only; indirect evidence for lorazepam. Comparator arms are not coadministration.
PK study is not a clinical sedation safety trial. Exact extract/species cannot resolve an unidentified valerian-root inventory item.
Source 4: original case report
pubmed.ncbi.nlm.nih.gov · Source check Sep 10, 2026
Population: One patient with generalized anxiety disorder.
Hand shaking, dizziness, throbbing and muscular fatigue were reported; authors suspected additive or synergistic activity.
How this applies: Exact lorazepam but identified V. officinalis plus passionflower does not resolve unknown inventory root species.
Both herbs were used together; cannot isolate passionflower, prove receptor mechanism or quantify risk. Abstract only; no coma or respiratory arrest established.
Research assessment: · Open full citations ↗
Review and change history
- Publication status
- Published research summary
- Clinical review
- Not yet recorded
| Date | Update |
|---|---|
| Article prepared | |
| Current exact available claims adjudicated using original captures and explicit identity and comparator limits. | |
| Research summary published |
Article revision: 5754f8eafde5baaa
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.