Elicit: Lavender Extract vs. Pharmacological Anxiety Treatments (public)

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. More on methods

Papers identified with Elicit search

Papers screened using:

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 (Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition) 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
Kasper et al., 2010 Randomized double-blind placebo-controlled trial with active control Silexan 80 mg/day, oral, 6–10 weeks Lorazepam 0.5 mg/day, placebo Subthreshold anxiety, generalized anxiety disorder, restlessness/agitation (DSM-IV) No
Kasper, 2013 Review (design not specified) Silexan 80/160 mg/day, oral, 6–10 weeks Lorazepam (dose not specified), placebo Subsyndromal anxiety, generalized anxiety disorder No
Yap et al., 2019 Systematic review and network meta-analysis of randomized controlled trials Silexan 80/160 mg/day, oral Paroxetine 20 mg/day, lorazepam 0.5 mg/day, placebo Anxiety disorders (various criteria) Yes
Kasper, 2015 Review of subgroup analyses of randomized controlled trials Silexan (dose not reported) Placebo Elderly (≥60) with anxiety disorders No
Bartova et al., 2025 Meta-analysis of randomized placebo-controlled trials Silexan 80 mg/day, oral Placebo Subthreshold anxiety, generalized anxiety disorder No
Schulz, 2010 Randomized double-blind comparative trial with active control Silexan (oral, dose not reported) Lorazepam (dose not reported) Generalized anxiety disorder (criteria not specified) No

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 (from 25 ± 4) No mention found
Kasper et al., 2014 Silexan 80/160 mg, paroxetine, placebo Hamilton Anxiety Rating Scale 160 mg: 14.1 ± 9.3; 80 mg: 12.8 ± 8.7; Paroxetine: 11.3 ± 8.0; Placebo: 9.5 ± 9.0 Silexan 80/160 mg vs. placebo: p < 0.01; Paroxetine vs. placebo: p = 0.10
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 Subthreshold: p < 0.001 (responders), p = 0.009 (remitters)

Safety and Adverse Events

Study Incidence of Adverse Events Types of Adverse Events Comparative Rates
Kasper et al., 2014 0.006–0.008 adverse events/day (Silexan), 0.011 (paroxetine), 0.008 (placebo) No mention found Silexan ≈ placebo < paroxetine
Kasper et al., 2018 Comparable to placebo Mild gastrointestinal symptoms, allergic skin reactions Lower than paroxetine, ≈ placebo
Yap et al., 2019 3% increase in gastrointestinal problems (Silexan vs. placebo) Gastrointestinal issues, headache Silexan > placebo (gastrointestinal), lorazepam (fatigue)

Conclusions