Lavender oil is available by prescription outside the US as Silexan and Lasea. The same manufacturer sells it over-the-counter in the US as CalmAid.
Most anxiety drugs beat placebo, but only one also beats it on side effects
STUDY: Müller TJ et al, European Archives of Psychiatry and Clinical Neuroscience 2026
STUDY TYPE: Network meta-analysis (systematic review)
FUNDING: Schwabe Pharma AG (manufacturer of silexan)
Background
Generalized anxiety disorder (GAD) and related anxiety conditions are usually treated with SSRIs or SNRIs, but side effects and dependency concerns with benzodiazepines push many patients toward alternatives. In the past 15 years, Silexan, an oral lavender oil capsule, has emerged as a viable alternative.
The Study
- 100 randomized trials, 28,637 adults with GAD or another anxiety disorder
- Compared 20 drugs, including SSRIs, SNRIs, benzodiazepines, a tricyclic, an atypical antipsychotic, and silexan, against placebo and each other
- Average treatment length was about 10 weeks
- Outcomes: anxiety scale (HAM-A) change, all-cause discontinuation, and adverse events
Nearly every drug beat placebo on the anxiety scale (HAM-A) except the benzo clobazam. Clomipramine had the best efficacy but the worst acceptability, with the highest dropout rate. Silexan (lavender oil) ranked sixth of 19 drugs for efficacy and was just as acceptable as placebo for dropouts.
Only four treatments caused fewer side effects than placebo on any measure: diazepam, agomelatine, clobazam, and silexan. When plotting efficacy against moderate side effects specifically, silexan was the only one of the thirteen most effective drugs to land in the good-efficacy, good-safety zone.
Limitations
Industry funded studies and review. Heterogeneity between studies was substantial, reporting gaps blocked analysis of response and remission rates.
Practice Implications
- There are a few examples where natural therapies surpass the effect size of medications. Silexan in GAD is one (marketed in the US as Calm Aid, 80 mg bid), confirmed by head-to-head trials and meta-analyses (in practice, I’ve seen a difference with it). It also has a tolerability advantage.
- The caveat is industry funding, a problem shared by pharmaceuticals.
—Chris Aiken, MD
Director, Psych Partners
Editor in Chief, Carlat Psychiatry Report
