Lavender Oil Shows Therapeutic Efficacy for Generalized Anxiety Disorder

by | May 6, 2019 | 2014, Botanicals, Brain Health, Essential Oils

Written by Angeline A. De Leon, Staff Writer. Lavender oil, at both high and low doses, significantly improved symptoms of anxiety in patients with generalized anxiety disorder compared to placebo and exhibited adverse events that were comparable to placebo and lower than for active paroxetine, the active control.

lavender essential oilAnxiety disorders constitute the most prevalent class of psychiatric disorders 1, with almost a quarter of patients with anxiety qualifying for generalized anxiety disorder (GAD) 2. Primarily characterized by excessive and uncontrollable feelings of anxiety and worry, GAD is most commonly treated using selective serotonin reuptake inhibitors 3. In alternative and holistic medicine, certain medicinal oils are recognized for their anxiolytic effects, lavender being one of the most well-known 4. Siloxane, an oral lavender product prepared from Lavandula angustifolia, is supported by evidence from clinical trials suggesting its ability to improve symptoms of anxiety in patients with subsyndromal anxiety, general restlessness, and/or agitation 5,6. A 2010 randomized study by Woelk and Schlafke 7 also demonstrated the clinical comparability of Silexan to standard prescription medication (lorazepam) in mitigating anxiety in GAD patients. A 2014 study 8 published in the International Journal of Neuropsychopharmacology sought to evaluate the clinical efficacy of Silexan in comparison to both placebo and another pharmacological first-line-of-treatment drug, paroxetine, in the treatment of GAD.

A total of 539 outpatients (aged 18-65 years) with a diagnosis of GAD (based on criteria of the Diagnostic and Statistical Manual of Mental Disorders 5) and a total score > 18 on the Hamilton Anxiety Scale (HAMA) were enrolled in a randomized, double-blind, double-dummy trial. Participants were randomized to one of four parallel groups, receiving 160 mg Silexan, 80 mg Silexan, 20 mg paroxetine, or placebo once daily for 10 weeks. Efficacy and safety assessments were performed every two weeks, with the primary measure of outcome being absolute decrease in HAMA total score from baseline to Week 10. Secondary measures such as the Hamilton Rating Scale for Depression and Clinical Global Impressions were also included.

For 160 mg Silexan, 80 mg Silexan, paroxetine, and placebo groups, HAMA total score was decreased by 14.1 +/- 9.3, 12.8 +/- 8.7, 11.3 +/- 8.0, and 9.5 +/- 9.0 points, respectively. Treatment response (defined as HAMA total score decrease by at least 50% of baseline value) and remission (defined as HAMA total score < 10 points at end of treatment) was highest in the high-dose Silexan group at a 60.3% and 46.3% rate, respectively, followed by low-dose Silexan (51.9% and 33.3%, respectively), paroxetine (43.2% and 34.1%, respectively), and placebo (37.8% and 29.6%, respectively). Both Silexan treatment groups were found to outperform placebo, the high-dose group showing superior efficacy starting Week 4 (mean value difference in total HAMA: 2.6 points, p = 0.01) and the low-dose group showing superiority starting Week 6 (mean value difference in total HAMA: 2.3 points, p = 0.02). Both Silexan groups also showed favorable differences over paroxetine in HAMA total score decrease between baseline and Week 10, with a mean value difference of 2.8 points (95% Confidence Interval: 0.7 to 4.9) for 160 mg Silexan and 1.6 points (95% CI: -0.3 to –3.5) for 80 mg Silexan. Compared to paroxetine, the prevalence rate of adverse events was 15.9% lower for the high-dose Silexan group and 6.1% lower for the low-dose Silexan group.

The present study, the first randomized trial examining Silexan in GAD, provides evidence supporting the safety profile and anxiolytic efficacy of the lavender oil preparation. Even at lower doses, Silexan proved to significantly reduce anxiety symptoms, showing superior performance over paroxetine. The higher-dose of Silexan was associated with the highest treatment response and remission rates overall. Notably, both doses of Silexan also led to fewer adverse reactions, as compared to paroxetine. Overall, findings from the study shed light on the clinical utility of Silexan as a means of mitigating GAD and improving quality of life. The present study could be further strengthened by the inclusion of more specific diagnostic instruments for the evaluation of GAD (e.g., Penn State Worry Questionnaire, General Anxiety Disorder-7 Test). It would also be interesting to evaluate the effects of Silexan on other forms of anxiety.

Source: Kasper S, Gastpar M, Muller WE, et al. Lavender oil preparation silexan effective in generalized anxiety disorder-a randomized, double-blind comparison to placebo paroxetine. International Journal of Neuropsychopharmacology. 2014; 17(6): 859-869. DOI: 10.1017/s146114544000017.

 © CINP 2014

Posted May 6, 2019.

Angeline A. De Leon, MA, graduated from the University of Illinois at Urbana-Champaign in 2010, completing a bachelor’s degree in psychology, with a concentration in neuroscience. She received her master’s degree from The Ohio State University in 2013, where she studied clinical neuroscience within an integrative health program. Her specialized area of research involves the complementary use of neuroimaging and neuropsychology-based methodologies to examine how lifestyle factors, such as physical activity and meditation, can influence brain plasticity and enhance overall connectivity.

References:

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  8. Kasper S, Gastpar M, Muller WE, et al. Lavender oil preparation Silexan is effective in generalized anxiety disorder–a randomized, double-blind comparison to placebo and paroxetine. The international journal of neuropsychopharmacology. 2014;17(6):859-869.