Wise Mind Herbs

The information on this page has been prepared with reference to published scientific literature, not by a medically qualified expert. It is not medical advice. Any decision to use a supplement or herb-based product is your responsibility. Consult a suitably qualified medical professional, especially if you have underlying conditions. Remember, nothing is for everyone, and not everything sold is what it claims to be. Some things work for some people, some of the time.

Lavender - Lavendula angustifolia

Lavender is one of the most studied aromatic plants in scientific literature, with numerous investigations into its therapeutic properties. This review examines the evidence-based health benefits of lavender from peer-reviewed scientific publications, focusing on efficacy, dosages, and safety considerations.

Botanical Information

The primary medicinal lavender species is Lavandula angustifolia (previously known as Lavandula officinalis), commonly called English lavender or true lavender. Other species include Lavandula stoechas (Spanish lavender), Lavandula latifolia (spike lavender), and Lavandula x intermedia (lavandin, a hybrid of L. angustifolia and L. latifolia). These species have different chemical compositions and potentially different therapeutic effects, though they are often confused in commercial products and some research.

Evidence-Based Health Benefits

Research supports lavender's efficacy for the following conditions:

• Anxiety disorders: Strongest evidence exists for oral lavender oil preparations in generalized anxiety disorder (GAD), with effects comparable to some benzodiazepines but without sedation or addiction risks.
• Mild to moderate depression: Several clinical trials show improvement in depression scores, particularly when used alongside conventional treatments.
• Sleep quality: Inhalation and oral administration have demonstrated improvements in sleep quality metrics, particularly in those with mild insomnia or anxiety-related sleep disturbances.
• Pain management: Studies show efficacy in reducing pain intensity in various conditions including migraine, dysmenorrhea, and post-operative pain.
• Wound healing: Topical applications have demonstrated antimicrobial properties and enhanced wound healing in controlled studies.

There is preliminary but less conclusive evidence for benefits in:

• Dementia-related agitation: Some studies suggest aromatherapy may reduce agitation in dementia patients.
• Premenstrual symptoms: Limited studies suggest inhaled lavender may reduce emotional symptoms.
• Mild inflammatory skin conditions: Some evidence supports anti-inflammatory effects in dermatitis and minor burns.

Dosages and Administration

Evidence-based dosages vary by preparation method:

• Oral preparations: The most studied is silexan (standardized to contain 25-46% linalool and 34-50% linalyl acetate), with effective dosages of 80-160 mg daily for anxiety disorders. Higher doses (160-240 mg) have been studied for more severe anxiety without increased adverse effects.
• Inhalation/aromatherapy: Typically 2-4 drops of essential oil in diffusers or 0.5-2% concentration in carrier mediums for 15-30 minutes, though standardization is lacking across studies.
• Topical application: Preparations ranging from 1-5% lavender essential oil in carrier oils or creams, applied 1-3 times daily to affected areas.
• Tea preparation: 1-2 teaspoons (1.5-4g) of dried flowers steeped in 8 oz hot water for 5-10 minutes, consumed 1-3 times daily.

Side Effects and Contraindications

Lavender is generally well-tolerated, but reported adverse effects include:

• Oral administration: Mild gastrointestinal complaints (nausea, constipation, dyspepsia) in 2-5% of patients, occasional headache, and rare allergic reactions.
• Topical application: Contact dermatitis in sensitive individuals, particularly with oxidized essential oils.
• Endocrine effects: Some research suggests lavender oil may have weak estrogenic and anti-androgenic activities, with case reports of prepubertal gynecomastia associated with topical products containing lavender oil, though causality remains debated.
• Drug interactions: Theoretical interactions with CNS depressants and CYP450 substrates, though clinical significance appears limited.

Contraindications include pregnancy (oral medicinal doses), known allergy to Lamiaceae plants, and caution in children under 12 years (for concentrated preparations).

Dosage Beyond Therapeutic Range

Studies investigating doses above the therapeutic range (>240 mg daily of standardized oral preparations) are limited. A few phase II trials have explored doses up to 320 mg without finding dose-limiting toxicity, but long-term safety data at these levels are lacking. This represents a significant knowledge gap in the literature. Animal toxicity studies suggest a wide safety margin, but human data on very high doses are insufficient to make evidence-based recommendations.

Conclusion

Lavender demonstrates well-established benefits for anxiety, with moderate evidence for sleep disorders and mild depression. The strongest evidence exists for standardized oral preparations like silexan, while aromatherapy applications show promise but suffer from methodological inconsistencies in research. Most studies demonstrate a favorable safety profile, though potential hormonal effects warrant further investigation. Significant knowledge gaps remain regarding optimal dosing, long-term effects, and comparative efficacy across different lavender species and preparation methods.

References

Cardia, G. F. E., Silva-Filho, S. E., Silva, E. L., Uchida, N. S., Cavalcante, H. A. O., Cassarotti, L. L., ... & Cuman, R. K. N. (2018). Effect of lavender (Lavandula angustifolia) essential oil on acute inflammatory response. Evidence‐Based Complementary and Alternative Medicine, 2018(1), 1413940.

Giovannini, D., Gismondi, A., Basso, A., Canuti, L., Braglia, R., Canini, A., ... & Cappelli, G. (2016). Lavandula angustifolia Mill. essential oil exerts antibacterial and anti-inflammatory effect in macrophage mediated immune response to Staphylococcus aureus. Immunological investigations, 45(1), 11-28.

Kasper, S., Müller, W. E., Volz, H. P., Möller, H. J., Koch, E., & Dienel, A. (2018). Silexan in anxiety disorders: Clinical data and pharmacological background. The world journal of biological psychiatry, 19(6), 412-420.

Kazemzadeh, R., Nikjou, R., Rostamnegad, M., & Norouzi, H. (2016). Effect of lavender aromatherapy on menopause hot flushing: A crossover randomized clinical trial. Journal of the Chinese Medical Association, 79(9), 489-492.

López, V., Nielsen, B., Solas, M., Ramírez, M. J., & Jäger, A. K. (2017). Exploring pharmacological mechanisms of lavender (Lavandula angustifolia) essential oil on central nervous system targets. Frontiers in pharmacology, 8, 280.

Matsumoto, T., Asakura, H., & Hayashi, T. (2013). Does lavender aromatherapy alleviate premenstrual emotional symptoms?: a randomized crossover trial. BioPsychoSocial medicine, 7, 1-8.

Ramsey, J. T., Li, Y., Arao, Y., Naidu, A., Coons, L. A., Diaz, A., & Korach, K. S. (2019). Lavender products associated with premature thelarche and prepubertal gynecomastia: case reports and endocrine-disrupting chemical activities. The Journal of Clinical Endocrinology & Metabolism, 104(11), 5393-5405.

Samuelson, R., Lobl, M., Higgins, S., Clarey, D., & Wysong, A. (2020). The effects of lavender essential oil on wound healing: A review of the current evidence. The Journal of Alternative and Complementary Medicine, 26(8), 680-690.

Sanna, M. D., Les, F., Lopez, V., & Galeotti, N. (2019). Lavender (Lavandula angustifolia Mill.) essential oil alleviates neuropathic pain in mice with spared nerve injury. Frontiers in pharmacology, 10, 472.