# Grindelia (Grindelia robusta)

*Gumweed, gum plant, California gum plant, hardy grindelia, scaly grindelia, rosin weed; *Grindelia robusta* Nutt., *Grindelia squarrosa* (Pursh) Dunal, *Grindelia humilis* Hook. & Arn., *Grindelia camporum* Greene; in pharmacy *Grindeliae herba**

**Known today as.** The dried flowering tops and leaves of several gumweeds of the western United States, of the family Asteraceae, perennial or biennial herbs or small shrubs whose early growth is “covered with a glutinous varnish.” Grieve describes round, yellow, smooth stems, alternate light-green, coarsely toothed leaves clasping the stem, and large solitary yellow flower-heads, the taste bitter and slightly aromatic; the drug may hold as much as 21 per cent of resins. Until the work of Perredes in 1906, she notes, the drug was thought to come from *Grindelia robusta*, which is in fact rarely used.

Kind: Plant

> **Caution.** Not for those allergic to plants of the Asteraceae (Compositae) family, nor under eighteen. The European agency advises seeing a doctor at once if the cough worsens or breathlessness, high fever, or purulent sputum appears.

## What was it used for?

A remedy for the chest. Grieve calls it “Expectorant and sedative, with an action resembling atropine,” its principal use “in bronchial catarrh, especially when there is any asthmatic tendency,” employed with success in whooping cough and outwardly for rhus poisoning and burns.

## What does modern science say?

The European Medicines Agency’s herbal committee accepts the herb as a traditional herbal medicine, “exclusively based upon long-standing use,” for the relief of cough associated with a cold (monograph of 2012). Its assessment report names triterpenoid saponins, phenolic acids such as chlorogenic acid, and about 5 per cent of tannins among the constituents, and accepted the use as plausible “Despite the absence of data from clinical studies.”

## Pharmacognosy and toxicology

- **triterpenoid saponins**: 
- **chlorogenic acid**: among the phenolic acids, with p-coumaric acid
- **tannins**: about 5 per cent
- **resins**: as much as 21 per cent of the drug, by Grieve’s account

**Mechanism.** Not established in the sources read for this entry.

**Standing.** European Union herbal monograph (2012): traditional use, “exclusively based upon long-standing use,” for cough associated with a cold.

## What lore surrounds it?

Of the officinal species Grieve distinguishes *G. cuneifolia*, a darker, less glutinous plant of marshes, from *G. squarrosa* of prairies and dry banks, whose involucral bracts spread outward.

## What did the older authorities say?

**Grieve, *A Modern Herbal* (1931).** “The plant was only made widely known to the medical profession in the latter part of the nineteenth century, by Dr. C. A. Canfield, and Mr. J. G. Steele of San Francisco.” It had also been recommended in cystitis and catarrh of the bladder; because its active principle leaves the body through the kidneys, it sometimes caused signs of kidney irritation.

## Sources

- Grieve, M. *A Modern Herbal*, “Grindelia.” As published on botanical.com.
- European Medicines Agency, Committee on Herbal Medicinal Products. *European Union herbal monograph on Grindeliae herba (Gumweed herb)*. EMA/HMPC/748220/2011, 20 November 2012.
- European Medicines Agency, Committee on Herbal Medicinal Products. *Assessment report on Grindeliae herba*. EMA/HMPC/748218/2011, 20 November 2012.
- European Medicines Agency, Committee on Herbal Medicinal Products. *European Union herbal monograph on Grindeliae herba (Gumweed herb)*. EMA/HMPC/748220/2011, 20 November 2012.
- European Medicines Agency, Committee on Herbal Medicinal Products. *Assessment report on Grindeliae herba*. EMA/HMPC/748218/2011, 20 November 2012.
- Grieve, M. *A Modern Herbal*, “Grindelia.” As published on botanical.com.

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*Grindelia.* In *Materia Medica*, edited by B. C. P. Statema. Version 1, revised 2026-10-17. The Thinking Press. https://thethinkingpress.org/materia-medica/grindelia

Historical description, not medical advice.