# Jalap (Ipomoea purga)

**Jalapa*; the root of Xalapa*

**Known today as.** *Ipomoea purga*, a Mexican morning glory whose tuber was shipped from the town of Xalapa.

Kind: Plant  
Poisoning: Gastrointestinal irritants (https://thethinkingpress.org/materia-medica/poisons/gastrointestinal)  
Toxic: yes

> **Caution.** A violent purge.

## What was it used for?

A strong purge, taken up in Europe in the seventeenth century and in every medicine chest by the eighteenth.

## What does modern science say?

Its resin is a drastic purgative; it has no place in medicine now.

## Pharmacognosy and toxicology

- **convolvulin**: 
- **jalapin**: 

**Mechanism.** As scammony.

**Dose.** Drastic; deaths in children.

**Standing.** Removed from the pharmacopoeias in the twentieth century.

## What lore surrounds it?

Benjamin Rush’s purging pills of calomel and jalap, his “thunderclappers,” went west with Lewis and Clark in 1804.

## Sources

- Pomet, P. (1694). *Histoire générale des drogues* (English, *A Compleat History of Druggs*, 1712).
- Grieve, M. (1931). *A Modern Herbal*, “Jalap.”
- Pomet, P. (1694). *Histoire générale des drogues*.

---

*Jalap.* In *Materia Medica*, edited by B. C. P. Statema. Version 1, revised 2026-09-30. The Thinking Press. https://thethinkingpress.org/materia-medica/jalap

Historical description, not medical advice.