# Deadly nightshade (Atropa belladonna)

*Belladonna; Italian *belladonna*, “beautiful lady”*

**Known today as.** *Atropa belladonna*, of the nightshade family.

Kind: Plant  
Poisoning: Tropane (anticholinergic) poisoning (https://thethinkingpress.org/materia-medica/poisons/anticholinergic)  
Toxic: yes

> **Caution.** Gravely poisonous in every part.

## What does modern science say?

Source of atropine, still used to dilate the pupil, to treat certain poisonings, and to steady a slowed heart. The berries are sweet and have killed children.

## Pharmacognosy and toxicology

- **atropine**: 
- **hyoscyamine**: 

**Mechanism.** Muscarinic blockade.

**Dose.** Two or three berries have killed a child, ten to twenty an adult.

**Standing.** Belladonna extracts survive in a few preparations; atropine is on the WHO list of essential medicines as an antidote and for the eye.

## What lore surrounds it?

Counted with henbane and mandrake among the herbs of the witches’ ointments.

The sixteenth-century Scottish historian George Buchanan credited Macbeth with poisoning the drink supplied to invading Danish troops during a truce with belladonna, after which his forces slaughtered them in their stupor. The episode is chronicle legend rather than documented history. Later writers have guessed belladonna for the poisons that Roman historians said Livia and Agrippina gave Augustus and Claudius; the sources themselves name figs and mushrooms.

## What did the older authorities say?

**Renaissance Italy.** The name is traditionally explained by women’s use of its juice to widen the pupils.

**Linnaeus.** Named the genus *Atropa* (1753) for Atropos, the Fate who cuts the thread of life.

## Sources

- Carl Linnaeus, *Species plantarum* (1753).
- IMSS (Museo Galileo), on belladonna.
- Goldfrank’s *Toxicologic Emergencies*, 11th ed. (2019).

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*Deadly nightshade.* In *Materia Medica*, edited by B. C. P. Statema. Version 1, revised 2026-09-25. The Thinking Press. https://thethinkingpress.org/materia-medica/deadly-nightshade

Historical description, not medical advice.