# Blue cohosh (Caulophyllum thalictroides)

*Pappoose root, squawroot, blueberry root; Omaha-Ponca *zhu-nakada-tanga-makaⁿ*, ‘great fever medicine’; Ojibwe *oci’g m c*; *Caulophyllum thalictroides* (L.) Michx.*

**Known today as.** *Caulophyllum thalictroides*, of the barberry family, Berberidaceae, a handsome perennial, smooth and glaucous, of rich, moist ground in swamps and beside streams in the United States and Canada, bearing small yellowish-green flowers in May and June and seeds the size of a large pea. The knotty root is the drug; its taste is sweetish-bitter, then acrid and pungent, and Grieve lists among its constituents a body like saponin.

Kind: Plant  
Toxic: yes

> **Caution.** That review records three case reports in which blue cohosh taken around delivery was linked to serious harm: a perinatal stroke; a heart attack with profound heart failure and shock; and severe injury to several organs from lack of oxygen. It records one report of abortifacient effect and laboratory evidence that it may harm the embryo and cause malformations, and finds its safety in breast-feeding unknown.

## What was it used for?

A remedy for women and for labour. Grieve calls it emmenagogue, antispasmodic, diuretic, diaphoretic, and anthelmintic, used in rheumatism, dropsy, epilepsy, hysteria, and uterine inflammation, and “preferable to Ergot, expediting delivery,” where labour was delayed by debility or fatigue. Smith found the Pillager Ojibwe using the root for female troubles, “especially for cramps in the stomach during painful menstruation.” A 2008 review cites a survey in which about 64 per cent of American midwives reported using it to help induce labour.

## What does modern science say?

No European monograph covers it, and no clinical trial of it was found for this entry. A systematic review of 2008 on its use in pregnancy and breast-feeding found only case reports and laboratory evidence, and concluded that it should be used with extreme caution in pregnancy, only under medical supervision, and should not be sold over the counter, calling for urgent studies of its safety among midwives who use it.

## Pharmacognosy and toxicology

- **saponin**: a body analogous to it, in Grieve’s list

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

**Standing.** There is no European monograph. A 2008 systematic review advised extreme caution in pregnancy, use only under medical supervision, and no over-the-counter sale.

## What lore surrounds it?

Grieve notes that the seeds were sometimes roasted and boiled to make a drink resembling coffee. Smith records the Eclectics’ claim that it would prevent miscarriage “by causing uterine contraction when uterine inertia is present.”

## What did the older authorities say?

**Gilmore, *Uses of Plants by the Indians of the Missouri River Region* (1919).** Among the Omaha and Ponca it was “great fever medicine,” a name built on their word for fever, literally ‘hot flesh.’ A decoction of the root was given for fevers, and “this was considered the most effectual febrifuge known to the Omaha.”

## Sources

- Grieve, M. *A Modern Herbal*, “Cohosh, Blue.” As published on botanical.com.
- Smith, H. H. (1932). *Ethnobotany of the Ojibwe Indians*, Blue Cohosh. Bulletin of the Public Museum of the City of Milwaukee 4. Project Gutenberg, 49527.
- Gilmore, M. R. (1919). *Uses of Plants by the Indians of the Missouri River Region*, “Caulophyllum thalictroides.” Thirty-third Annual Report of the Bureau of American Ethnology. Internet Archive, usesofplantsbyin00gilm.
- Dugoua JJ, et al. (2008). Safety and efficacy of blue cohosh (Caulophyllum thalictroides) during pregnancy and lactation. *The Canadian journal of clinical pharmacology = Journal canadien de pharmacologie clinique*. PMID 18204101.
- Grieve, M. *A Modern Herbal*, “Cohosh, Blue.” As published on botanical.com.
- Dugoua JJ, et al. (2008). Safety and efficacy of blue cohosh (Caulophyllum thalictroides) during pregnancy and lactation. *The Canadian journal of clinical pharmacology = Journal canadien de pharmacologie clinique*. PMID 18204101.

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

Historical description, not medical advice.