# Rosemary (Salvia rosmarinus)

**Ros marinus*, “dew of the sea”*

**Known today as.** *Salvia rosmarinus* (formerly *Rosmarinus officinalis*).

Kind: Plant  
Qualities: Hot and dry in the second degree (Galenic tradition).  
Poisoning: Convulsant terpenes (thujone, pinocamphone, camphor) (https://thethinkingpress.org/materia-medica/poisons/convulsant-terpenes)

## What was it used for?

For the head and the memory, the palsy, and the weak stomach; burnt in sickrooms and churches as a cheap incense; the chief herb of Hungary water.

## What does modern science say?

Its carnosic acid and oil are antioxidant and antimicrobial in the laboratory; claims for memory rest on small studies. Its scent, breathed, improved speed on memory tasks in small studies at Northumbria University, and under a gram of the dried herb improved memory scores in one small trial of the elderly, while six grams impaired them; the oil in quantity can provoke seizures. Rosemary extract is now an approved antioxidant in foods.

## Pharmacognosy and toxicology

- **1,8-cineole**: 
- **camphor**: 
- **rosmarinic acid**: 
- **carnosic acid and carnosol**: the antioxidant diterpenes

**Mechanism.** The oil on the skin is a rubefacient and counter-irritant, the Hungary water use; cineole in the breath raised alertness and memory scores in small trials of inhaled rosemary (Moss, 2003), which gives Ophelia’s remembrance a laboratory footnote; carnosic acid is a food antioxidant (E392). The oil in quantity is a convulsant by its camphor.

**Dose.** The herb is safe; the oil swallowed at a few millilitres has caused seizures; not for epileptics.

**Standing.** EMA monographs (2011) for the leaf for dyspepsia and the oil for minor muscular pain and circulatory complaints, on tradition.

## What lore surrounds it?

“There’s rosemary, that’s for remembrance,” says Ophelia. Carried at weddings and laid on coffins, it stood for fidelity and for memory of the dead. See [Hungary water](https://thethinkingpress.org/materia-medica/hungary-water).

Sir Thomas More let it run over his garden walls “because it is the herb sacred to remembrance, and therefore to friendship.” Sprigs are worn on Anzac Day in Australia, since rosemary grows wild on the Gallipoli peninsula.

## What did the older authorities say?

**Dioscorides.** Gives *libanotis*, the rosemary, as warming, for the jaundice and before exercise, and the Romans burned it in rites where incense was too dear.

**Charlemagne.** Ordered it grown on the imperial farms in the *Capitulare de villis* of about 800, and the monasteries kept it; it reached England before the Conquest, and Queen Philippa’s mother sent her cuttings from Antwerp in 1338 with a treatise on its virtues.

**The Greek students.** Wore garlands of it at their examinations to strengthen the memory, a custom still invoked by its sellers.

## Sources

- Gerard, J. (1597). *The Herball*.
- Shakespeare, *Hamlet* IV.5.
- Grieve, M. *A Modern Herbal*, “Rosemary.” As published on botanical.com.
- Moss, M., et al. (2003). “Aromas of rosemary and lavender essential oils differentially affect cognition and mood.” *International Journal of Neuroscience* 113.
- *Capitulare de villis* (c. 800).
- EMA/HMPC (2011). *Community herbal monograph on Rosmarinus officinalis L., folium* (EMA/HMPC/457257/2010).
- Moss, M., et al. (2003). “Aromas of rosemary and lavender essential oils differentially affect cognition and mood in healthy adults.” *International Journal of Neuroscience* 113.

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*Rosemary.* In *Materia Medica*, edited by B. C. P. Statema. Version 1, revised 2026-10-01. The Thinking Press. https://thethinkingpress.org/materia-medica/rosemary

Historical description, not medical advice.