A large multi-center trial using four arms for 10 weeks is adding excitement and support for an adored herb—lavender. This is the largest trial of oral lavender supplementation ever conducted. The results are truly impressive. Lavela WS 1265 was evaluated at 160 mg and 80 mg against placebo and a conventional agent for promoting contentment.
Each softgel of WS 1265 is 80 mg of essential lavender oil so the study used 1 or 2 softgels depending upon the arm. The primary tool used to evaluated efficacy was the Hamilton Anxiety Rating Scale (HAM-A total score) to monitor changes in the level of tension and relaxation beginning at baseline through week 10 of the trial. A total of 539 female (71.4%) and male (28.6%) subjects 18-65 years of age were randomized into groups. Participants were eligible for the study if they met the inclusion criteria of a HAM-A total score of equal to or greater than 18. Two arms of the trial evaluated WS 1265: one at 80 mg per day and another at 160 mg per day. A third arm received the conventional approach and a fourth arm received a placebo. The clinical results demonstrated that WS 1265 was superior to the conventional approach. The HAM-A total score decreased by 14.1±9.3 in the 160 mg group, 12.8±8.6 in the 80 mg group, 11.3±8.0 and 9.5±9.0 for the conventional and placebo group respectively.1
Conventional approaches have mean HAM-A reductions in the range of 11 to 15.3 points, suggesting comparable to efficacy of oral lavender oil in this study.2,3,4,5
Application of use
Lavender has mainly been used in aromatherapy, but since this study used oral lavender oil, the same conclusions cannot be made using olfactory or topical administration. Used in this study was Silexan (Lavela WS 1265) a novel, well-deﬁned preparation from Lavandula angustifolia for oral use. The parameters of the essential oil follow the monograph Lavender oil of the European Pharmacopoeia. 6
Providing two different doses of WS 1265 allows more flexibility in evidence-based clinical dosing as well. Previous studies showed similar positive results with 80 mg against placebo and similar reduction in HAM-A scores against a different conventional approach.1,2
It appears the mechanism of action is inhibition of voltage dependent calcium channels (VOCCs).7 An interaction study showed that repeated WS 1265 administration at a dose of 160 mg per day has no clinically relevant inhibitory or inducing effects on several cytochrome P450 enzymes.8 Oral lavender appears quite safe. Of particular interest in the secondary findings of this study was tolerability in which adverse events in the lavender groups were similar to placebo (4.4% in the 160 mg group and 4.5% in the 80 mg group) and were primarily limited to mild gastrointestinal distress. In my practice, the same seems to be true. However, some of these effects are repeating of the oil the same effect fish oil can have but lavender oil tastes much better and is not offensive at all to some patients.
Withdrawal from conventional and even some alternative approaches is a real concern. Discontinuation or reduction in dosages of conventional approaches should only be done by the appropriate practitioner. It does not appear that oral lavender has these same challenges.
Limitations of the study
Lavender was only studied against one dosage of the conventional approach. This study relied on questionnaires which is a limitation but also accurately reflects common practices. You can see that there is a broad range of responses to each arm of this trial which is more a limitation of the evaluation techniques used and the type of subject recruited for the study.
1. Kasper S et al. Int J Neuropsychopharmacol. 2014 Jun;17(6):859-69.
2. Kasper S et al. Int Clin Psychopharmacol. 2010 Sep;25(5):277-87.
3. Woelk H et al. Phytomedicine. 2010 Feb;17(2):94-9.
4. Bielski RJ et al. Ann Clin Psychiatry. 2005 Apr-Jun;17(2):65-9.
5. Allgulander C et al. Curr Med Res Opin. 2007 Jun;23(6):1245-52.
6. European Directorate for the Quality of Medicines and Healthcare (2005) Lavender oil. In: European Pharmacopoeia 5.0, p1894. Strasbourg, European Directorate for the Quality of Medicines & HealthCare.
7. Schuwald AM et al. PLoS One. 2013 Apr 29;8(4):e59998
8. Doroshyenko O et al. Drug Metab Dispos. 2013 May;41(5):987-93.