Lamiaceae
Lavandula angustifolia
Lavender · English lavender · True lavender
- Part used
- floweroil
- Native range
- The western Mediterranean, chiefly Provence and the Pyrenees
- Morphology
- A grey-green woody subshrub to a metre with narrow leaves and short spikes of small violet flowers on long stems. Distinguished from lavandin, the sterile hybrid grown for most commercial oil.
- Also known as
- Lavandula officinalis
What is in it
Evidence
One of the better-supported entries here. Silexan, a standardised oral lavender oil preparation, has multiple randomised trials showing benefit in anxiety comparable to some conventional treatments, and is a registered medicine in Germany. Aromatherapy trials for sleep are much weaker.
Safety
Generally well tolerated. Oral preparations cause eructation with a lavender taste, which is the commonest complaint and makes blinding difficult. Case reports associate topical lavender and tea tree oils with prepubertal gynaecomastia; the finding is contested and not established. The oil is a common contact allergen, particularly once oxidised.
Interactions: Additive sedation with CNS depressants
Regulatory: Permitted as a food and as a listed medicine ingredient. Silexan is a registered medicine in several European markets.
How the traditions classify it
Three systems, rating the same plant. Where they disagree, none of them is correcting the others — they are separate frameworks that arrived at their categories independently.
Historical use
Used across Europe for headache, nervousness and sleep, and heavily as a strewing herb, in bathing and in perfumery. The medicinal reputation is old; the oral preparation is recent.
Recorded as history and attributed where possible. Long use establishes that a plant was widely used, not that it worked, and not that it was safe.
Worth knowing
Lavender is the clearest case in this collection of the difference between a traditional plant and a pharmaceutical product made from it.
The oral preparation with good anxiety trials is a specific, standardised, capsule-encapsulated oil developed and tested as a medicine. The evidence belongs to that product. It does not transfer to a lavender pillow spray, a bath oil or a diffuser, and it is routinely used to imply that it does.
Most commercial lavender oil is not even this species. It is lavandin — Lavandula × intermedia, a sterile hybrid with true lavender — which yields far more oil per hectare, smells sharper because of higher camphor, and is a different product.
Nomenclature verified against GBIF backbone taxonomy.