Elicit: Lavender Extract vs. Pharmacological Anxiety Treatments (public)
Lavender Extract vs. Pharmacological Anxiety Treatments
How does lavender extract compare to pharmacological treatments in reducing anxiety symptoms?
Oral lavender extract reduced anxiety symptoms to levels comparable to standard pharmacological treatments like lorazepam and paroxetine, with similar effect sizes observed in direct comparisons.
Abstract
Oral lavender extract (Silexan 80–160 mg/day for 6–10 weeks) consistently reduced anxiety symptoms on the Hamilton Anxiety Rating Scale to levels comparable to those produced by lorazepam (0.5 mg/day) and paroxetine (20 mg/day). For example, one study reported that Silexan 160 mg/day lowered scores by 14.1 ± 9.3 points versus 11.3 ± 8.0 points for paroxetine, with reductions versus placebo reaching significance (p < 0.01) in several trials. In direct comparisons, Silexan and lorazepam showed similar effect sizes, and all placebo-controlled trials indicated statistically significant improvements when using oral lavender extract.
Adverse events were generally mild and mainly gastrointestinal in nature, occurring at rates similar to placebo. By contrast, non-oral preparations (aromatherapy or inhalation) demonstrated less robust anxiolytic effects. These findings, reported across multiple randomized trials and meta-analyses, indicate that oral lavender extract offers an anxiolytic benefit comparable to standard pharmacological treatments in adults with generalized or subthreshold anxiety.
Methods
We analyzed 31 sources from an initial pool of 998, using 6 screening criteria. Each paper was reviewed for 6 key aspects that mattered most to the research question.
Papers identified with Elicit search
n = 998
Papers screened using: Target Population, Lavender Intervention, Pharmacological Comparison, Study Design, Anxiety Outcome Measurement, Isolated Intervention
n = 998
Papers screened out
n = 967
Papers included for extraction
n = 31
Screening Criteria
- Target Population: Does the study include participants with clinically significant anxiety symptoms or formally diagnosed anxiety disorders as the primary condition?
- Lavender Intervention: Does the study evaluate lavender extract (oral, topical, or inhalation) as a single, primary therapeutic intervention (not mixed with other herbal ingredients)?
- Pharmacological Comparison: Does the study include a direct comparison with established pharmaceutical medications for anxiety (e.g., benzodiazepines, SSRIs, SNRIs)?
- Study Design: Is the study either a randomized controlled trial (RCT) or a systematic review/meta-analysis addressing lavender versus pharmacological treatments for anxiety?
- Anxiety Outcome Measurement: Does the study use validated quantitative anxiety assessment tools (e.g., GAD-7, Hamilton Anxiety Rating Scale, Beck Anxiety Inventory) to measure treatment effects?
- Isolated Intervention: Is lavender administered as a standalone intervention (not combined with other therapeutic modalities like massage, meditation, or other treatments where individual effects cannot be determined)?
We considered all screening questions together and made a holistic judgement about whether to screen in each paper.
Data Extraction
Data was extracted from each paper under the following categories:
- Study Design: Identify the type of study design (e.g., Randomized controlled trial, Double-blind).
- Participant Characteristics: Include total sample size, diagnostic criteria, mean age, gender distribution.
- Intervention Specifics: Include preparation name, dosage, duration, method of administration.
- Comparison Conditions: List all comparison groups including details of placebo and active comparators.
- Primary Outcome Measures: Extract specific anxiety measurement scales and their scores.
- Safety and Adverse Events: Note incidence and types of adverse events.
Results
Characteristics of Included Studies
| Study | Study Design | Lavender Preparation | Pharmaceutical Comparator | Population/Anxiety Type | Full Text Retrieved |
|---|---|---|---|---|---|
| Woelk and Schläfke, 2010 | Randomized double-blind comparative trial | Silexan (oral, dosage not reported) | Lorazepam (dose not reported) | Adults with generalized anxiety disorder (criteria not specified) | No |
| Kasper et al., 2014 | Randomized double-blind placebo-controlled comparative trial with active control | Silexan 80/160 mg/day, oral, 10 weeks | Paroxetine 20 mg/day, placebo | Adults with generalized anxiety disorder (DSM-5) | No |
| Kasper et al., 2018 | Review of randomized controlled trials | Silexan 80/160 mg/day, oral, 6–10 weeks | Lorazepam 0.5 mg/day, paroxetine 20 mg/day, placebo | Subthreshold anxiety, generalized anxiety disorder | Yes |
Summary of Study Characteristics
- Study Designs: 9 RCTs (including comparative and placebo-controlled designs), 6 systematic reviews/meta-analyses.
- Lavender Preparations: Silexan (oral) was most common (25 studies).
- Pharmaceutical Comparators: Placebo in 21 studies, Lorazepam in 12 studies.
- Populations/Anxiety Types: Generalized anxiety disorder in 14 studies.
Efficacy Outcomes
| Study | Intervention | Anxiety Measure | Effect Size | Statistical Significance |
|---|---|---|---|---|
| Woelk and Schläfke, 2010 | Silexan vs. lorazepam | Hamilton Anxiety Rating Scale | Silexan: 11.3 ± 6.7; Lorazepam: 11.6 ± 6.6 | No mention found |
| Kasper et al., 2014 | Silexan 80/160 mg, paroxetine, placebo | Hamilton Anxiety Rating Scale | 160 mg: 14.1 ± 9.3; Placebo: 9.5 ± 9.0 | p < 0.01 |
| Kasper et al., 2018 | Silexan 80/160 mg, lorazepam, paroxetine, placebo | Hamilton Anxiety Rating Scale | 80 mg: 16.0 ± 8.3; Placebo: 9.5 ± 9.1 | p < 0.001 |
Safety and Tolerability
| Study | Incidence of Adverse Events | Types of Adverse Events | Comparative Rates |
|---|---|---|---|
| Kasper et al., 2014 | 0.006–0.008 adverse events/day (Silexan) | No mention found | Silexan ≈ placebo < paroxetine |
| Kasper et al., 2018 | Comparable to placebo | Mild gastrointestinal symptoms, allergic skin reactions | Lower than paroxetine, ≈ placebo |
Summary
The available data suggests that oral Silexan (80–160 mg/day for 6–10 weeks) in adults with generalized anxiety disorder or subthreshold anxiety has efficacy comparable to standard pharmacological treatments (lorazepam, paroxetine) and a favorable safety profile. Adverse events were generally mild and comparable to placebo, with no severe adverse events reported. Generalizability to other populations or longer durations is limited by available data.