No weight gain or loss during 10 weeks of treatment with lavender oil preparation Silexan in patients with anxiety disorders

Introduction

Certain anxiolytics and antidepressants can induce weight gain due to their capacity to influence appetite, metabolism, and hormonal function, particularly when administered over an extended duration. The most significant increase in weight has been associated with tricyclic antidepressants, maprotiline, mirtazapine, paroxetine, as well as pregabaline. Weight changes as an adverse effect may lead to the discontinuation of therapeutic interventions by the patient. Ten weeks of treatment with Silexan1, a proprietary essential oil from Lavandula angustifolia, at a daily dose of 80 mg was shown to be significantly more efficacious than placebo in the reduction of anxiety and co-occuring depressive and psychosomatic symptoms. The present work sought to ascertain the impact of a 10-week course of Silexan treatment on weight. To this end, a pooled data analysis of all placebo-controlled clinical trials involving Silexan in the treatment of anxiety disorders was conducted.

Methods

The analysis based on five placebo-controlled clinical trials. During each trial, patients took 80 mg of Silexan daily over a period of 10 weeks. The endpoints encompassed the patients’ weight change between the commencement of the trial and the individual treatment end, the rate of patients who exhibited weight loss of at least 2 kg, and the rate of patients who exhibited weight gain of at least 2 kg during the treatment period. The pre-defined subgroups were categorised as follows: sex, age (with the median as the cut-off point), and body mass index (BMI, with the cut-off point set at 25 kg/m²). Meta-analyses with fixed effect models were applied since safety endpoints were analysed. Mean differences were estimated for the continuous outcome and risk differences were calculated for binary endpoints.

Results

The study population comprised 1,180 patients (Silexan 594, placebo 586). The mean difference in weight after 10 weeks of treatment was 0.10 kg (95% CI -0.08; 0.28), which was not statistically significant (p=0.2794). The rate of patients exhibiting a weight increase of at least 2 kg at the end of the treatment was found to be comparable between both treatment groups (difference of 0.02, 95% CI -0.02; 0.05, p=0.3734). The same holds true for the rate of patients exhibiting weight loss of at least 2 kg (difference of 0.00, 95% CI -0.04; 0.03, p=0.8441). In the evaluation of subgroups, results were consistent with those of the entire study population. An influence of factors such as sex, age, and BMI on weight change during the treatment period was not observed.

Conclusions

During a 10-week treatment period, a dosage of 80 mg of Silexan daily did not demonstrate any tendency towards weight gain or loss in patients diagnosed with anxiety disorders. In the overall view with previous results on efficacy and safety, Silexan is a promising therapeutic option, both effective and safe, and thus a valuable alternative to synthetic preparations.

References

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