Lavender (Lavandula angustifolia)

Lavandula angustifolia
Evidence Level
Strong
2 Clinical Trials
4 Documented Benefits
4/5 Evidence Score

Lavender is an aromatic Mediterranean herb whose flowers and essential oil have been used for millennia for their calming, sleep-promoting, and anxiolytic properties. Unlike most aromatherapy ingredients, oral lavender oil has been tested in rigorous clinical trials — with Silexan® (Lasea®, Spitzner), a licensed oral lavender oil preparation, demonstrating pharmaceutical-grade efficacy for generalized anxiety disorder in multiple RCTs. Silexan® is the first orally administered essential oil approved as a prescription medicine for anxiety in Germany.

Studied Dose 80 mg/day Silexan® oral lavender oil for anxiety/sleep; aromatherapy: 2–4% lavender essential oil in diffuser or topical application
Active Compound Linalool (25–38%) and linalyl acetate (25–45%) — Silexan® by Dr. Willmar Schwabe GmbH (clinically standardized oral lavender oil, 80 mg/capsule) is the evidence-based form

Benefits

Generalized anxiety disorder treatment

Silexan® 80 mg/day has demonstrated anxiolytic efficacy comparable to lorazepam 0.5 mg/day in a head-to-head RCT — without sedation, dependence risk, or cognitive impairment. Multiple large RCTs (including 539-patient and 318-patient trials) confirm significant reductions in Hamilton Anxiety Rating Scale scores, with effects appearing within 2 weeks.

Sleep quality improvement

Oral Silexan® significantly improves sleep quality, reduces sleep onset latency, and improves next-day functioning in adults with anxiety-related sleep disturbances. Unlike benzodiazepines and Z-drugs, lavender improves sleep architecture without suppressing deep sleep or REM stages, and produces no morning grogginess or rebound insomnia.

Mixed anxiety-depression improvement

Silexan® demonstrates efficacy for both anxiety and depressive components of mixed anxiety-depression disorder — producing significant improvements on both HAM-A and Montgomery-Åsberg Depression Rating Scales. The multi-neurotransmitter mechanism explains effects across both mood dimensions simultaneously.

Aromatherapy stress and relaxation effects

Inhaled lavender aromatherapy significantly reduces subjective anxiety, cortisol levels, and autonomic stress responses (heart rate, blood pressure) in acute stress studies. Effects are rapid — occurring within minutes of inhalation — through olfactory pathway-mediated limbic system modulation.

Mechanism of action

1

GABA-A receptor modulation

Linalool and linalyl acetate act as positive allosteric modulators at GABA-A receptors — enhancing inhibitory GABAergic neurotransmission without the sedative, amnesic, or dependency-producing effects of benzodiazepines. The binding site differs from benzodiazepines, explaining the absence of tolerance, dependence, and cognitive impairment.

2

Voltage-gated calcium channel inhibition

Lavender oil constituents inhibit voltage-gated calcium channels in neurons, reducing neuronal excitability and the hyperactivation of anxiety circuits in the amygdala and prefrontal cortex. This mechanism contributes to anxiolytic effects independently of GABA-A receptor modulation.

3

5-HT1A receptor partial agonism

Linalool acts as a partial agonist at 5-HT1A (serotonin type 1A) receptors — the same receptor targeted by buspirone (a non-benzodiazepine anxiolytic) and implicated in the mechanisms of SSRIs. 5-HT1A activation reduces anxiety and depressive symptoms through autoreceptor-mediated serotonin modulation in the raphe nucleus.

Clinical trials

1
Silexan® vs Lorazepam for GAD — Head-to-Head RCT
PubMed

Randomized, double-blind, active-controlled trial of Silexan® (80 mg/day standardized lavender oil) vs lorazepam (0.5 mg/day) vs placebo in 77 generalized anxiety disorder patients for 6 weeks. (Woelk & Schläfke 2010, Phytomedicine)

77 GAD patients. 6-week head-to-head.

Silexan® produced equivalent anxiolytic efficacy to lorazepam (HAM-A reduction: -11.3 vs -11.7 points). No sedation, no cognitive impairment, no abuse potential — important advantages over benzodiazepines. Critical context: this is a relatively striking result for a botanical — and Silexan® is approved as a pharmaceutical (Lasea®) in Germany and several European countries. The evidence base is unusual for a 'supplement' — closer to pharmaceutical-grade evidence.

2
Silexan® for GAD — Large Pivotal RCT

Large randomized, double-blind, placebo-controlled trial of Silexan® (80 or 160 mg/day) vs placebo in 539 adults with subsyndromal anxiety / GAD for 10 weeks. (Kasper et al. 2014, Int Clin Psychopharmacol)

539 anxiety patients. 10-week intervention.

Silexan® significantly reduced HAM-A total score, somatic and psychic anxiety subscores, and improved sleep quality and quality of life vs placebo. Dose-response observed. Generally well-tolerated; mild eructation/burping (lavender 'burps') is the most common side effect. Larger and more rigorous evidence than most botanical anxiolytics.

Side effects and drug interactions

Common Potential side effects

Oral lavender oil (Silexan®): mild GI effects (nausea, burping with lavender odor) in small percentage
No sedation, cognitive impairment, or dependency — key advantage over benzodiazepines
Not recommended for prepubertal boys — lavender has mild estrogenic activity; case reports of gynecomastia with topical lavender oil exposure

Important Drug interactions

CNS depressants (benzodiazepines, alcohol, opioids) — mild additive sedative effects possible; use cautiously
CYP3A4 substrates — lavender oil mildly inhibits CYP3A4; monitor medications with narrow therapeutic windows
Antidepressants — 5-HT1A agonism may interact with SSRI/SNRI therapy; generally safe at standard doses but monitor mood carefully

Frequently asked questions about Lavender (Lavandula angustifolia)

How much lavender should I take?

Oral lavender oil studied for calm and relaxation (the standardized preparation Silexan) uses 80 mg per day. Lavender is also used as a tea, in aromatherapy, and as an essential oil for topical (diluted) or diffuser use.

What is lavender used for?

Lavender is best known for promoting calm, easing occasional anxiousness, and supporting sleep and relaxation. It is used orally (as a standardized oil capsule), in aromatherapy, and topically in diluted form.

Does lavender aromatherapy actually work?

Some studies suggest lavender aromatherapy may modestly support relaxation and sleep quality, and oral standardized lavender oil has research for easing occasional anxiousness. Effects are gentle, making it a popular part of a wind-down routine.

Is lavender safe?

Oral and aromatherapy lavender are generally well tolerated; oral capsules can cause mild burping with a lavender taste. Essential oil must be diluted for skin and never swallowed unless it is a product made for oral use. Check with a doctor if pregnant or on sedatives.

What is Lavender?

Lavender is an aromatic Mediterranean herb whose flowers and essential oil have been used for millennia for their calming, sleep-promoting, and anxiolytic properties.

What is the recommended dosage of Lavender?

The clinically studied dose is 80 mg/day Silexan® oral lavender oil for anxiety/sleep; aromatherapy: 2–4% lavender essential oil in diffuser or topical application Always follow the product label and check with a healthcare provider for personal advice.

Is Lavender safe, and does it have side effects?

For most healthy adults, Lavender is well tolerated at studied doses. Reported effects can include: Oral lavender oil (Silexan®): mild GI effects (nausea, burping with lavender odor) in small percentage No sedation, cognitive impairment, or dependency — key advantage over benzodiazepines It may also interact with some medications. Lavender is not right for everyone, so check with a healthcare provider first if you are pregnant or breastfeeding, have a medical condition, or take prescription medication.

Does Lavender interact with any medications?

Possible interactions include: CNS depressants (benzodiazepines, alcohol, opioids) — mild additive sedative effects possible; use cautiously CYP3A4 substrates — lavender oil mildly inhibits CYP3A4; monitor medications with narrow therapeutic windows If you take prescription medication, check with a pharmacist or doctor before using it.

How strong is the scientific evidence for Lavender?

NutraSmarts rates the evidence for Lavender as Strong (4 out of 5). It is backed by 2 clinical trials and 4 cited references summarized on this page. A higher rating reflects more, larger, and better-designed human studies.

References(4 citations)

Evidence ratings on NutraSmarts are based on the totality of human clinical research, with emphasis on randomized controlled trials, meta-analyses, and systematic reviews. The references below directly support claims made throughout this page.

  1. Kasper S, Gastpar M, Muller WE, Volz HP, Moller HJ, Dienel A, et al. Silexan, an orally administered Lavandula oil preparation, is effective in the treatment of 'subsyndromal' anxiety disorder: a randomized, double-blind, placebo controlled trial. Int Clin Psychopharmacol. 2010;25(5):277-87. doi: 10.1097/YIC.0b013e32833b3242.PubMedUsed to support: Supports oral-Silexan anxiety claim: landmark RCT showing oral lavender oil (Silexan 80 mg/day) significantly reduced anxiety versus placebo in subsyndromal anxiety disorder, with good tolerability. Core evidence that oral Silexan (not aromatherapy) is effective.
  2. Kasper S, Gastpar M, Muller WE, Volz HP, Moller HJ, Schlafke S, et al. Lavender oil preparation Silexan is effective in generalized anxiety disorder - a randomized, double-blind comparison to placebo and paroxetine. Int J Neuropsychopharmacol. 2014;17(6):859-69. doi: 10.1017/S1461145714000017.PubMedUsed to support: Supports stronger oral-Silexan claim: in generalized anxiety disorder, Silexan was superior to placebo and showed efficacy comparable to paroxetine, with fewer typical antidepressant side effects. Strengthens the case that oral lavender oil rivals standard low-dose anxiolytic therapy.
  3. Woelk H, Schlafke S. A multi-center, double-blind, randomised study of the Lavender oil preparation Silexan in comparison to Lorazepam for generalized anxiety disorder. Phytomedicine. 2010;17(2):94-9. doi: 10.1016/j.phymed.2009.10.006.PubMedUsed to support: Supports oral-Silexan-vs-benzodiazepine claim: in GAD, Silexan was comparable to lorazepam in reducing anxiety, without sedation or dependence potential. Note the main reported side effect of oral lavender oil is eructation (lavender 'burp').
  4. Donelli D, Antonelli M, Bellinazzi C, Gensini GF, Firenzuoli F. Effects of lavender on anxiety: A systematic review and meta-analysis. Phytomedicine. 2019;65:153099. doi: 10.1016/j.phymed.2019.153099.PubMedUsed to support: Honest framing of aromatherapy vs oral: meta-analysis concluding the strongest evidence is for oral Silexan, while inhaled/aromatherapy lavender showed weaker and less consistent anxiolytic effects. Supports framing oral Silexan as better-evidenced than aromatherapy.