Butterbur
Petasites; pestilence wort, German Pestwurz
- Known today as
- Petasites hybridus, of the daisy family, with huge rhubarb-like leaves in damp places.
- Kind
- Plant, in 1 older authority
- Constituents
- petasin, senecionine
- Earliest authority here
- Gerard
- In other databases
- Plants of the World Online search · GBIF search · Wikidata search
Caution. The unprocessed plant is toxic to the liver.
Butterbur: what was it used for?
Against the plague and pestilential fevers, the root in powder or wine; for the stone, the cough, and worms.
Butterbur: what does modern science say?
A purified extract prevented migraines in controlled trials, but the raw plant contains pyrrolizidine alkaloids that injure the liver, and concern about liver harm has since made neurologists cautious of it.
Butterbur: is it poisonous?
Yes, in some form or dose. The unprocessed plant is toxic to the liver. Its poisoning is pyrrolizidine alkaloids (veno-occlusive disease): Weeks to months of use. Historical description, not medical advice; in a poisoning, call a poison centre.
Pharmacognosy & Toxicology
- Constituents
- petasin ChEMBLthe active sesquiterpene
- senecionine ChEMBLa pyrrolizidine alkaloid
- Mechanism
- Petasins block calcium channels and leukotriene synthesis; the alkaloids injure the liver.
- Checked against ChEMBL
- petasin: No measurement in ChEMBL for “block calcium channels and leukotriene synthesis” (38 activities recorded, none against the target named); the line rests on its references.
- Toxic dose
- Cumulative from the raw plant; the purified extract is alkaloid-free.
- Syndrome
- Pyrrolizidine alkaloids (veno-occlusive disease)
- Standing
- A purified extract prevented migraine in trials; withdrawn in Britain in 2012 over liver cases, and advised against by the American Academy of Neurology since 2015.
- Lipton, R. B., et al. (2004). “Petasites hybridus root (butterbur) is an effective preventive treatment for migraine.” Neurology 63. Verified against its record · doi:10.1212/01.wnl.0000147290.68260.11
The abstract of each source, beneath its citation. For Club members. About the Club or sign in.
Constituent names open the compound’s record at PubChem, and “ChEMBL” beside a name opens its record at ChEMBL, the European Bioinformatics Institute’s database of bioactive molecules. Where a mechanism line was checked against ChEMBL (ChEMBL 37, read 1 October 2026), the check is shown with the measured value and its source paper, or says plainly that nothing has been measured. Doses are as the references give them, for description only; this is not medical advice. Each source carries the result of its check against Crossref, PubMed, or the authority’s page: see Verification.
Butterbur: what lore surrounds it?
Its great leaves were used to wrap butter in the heat of summer, hence its English name.
Butterbur: what did the older authorities say?
- Gerard
- Calls it a sovereign medicine against the plague and pestilent fevers.
Sources
- Gerard, J. (1597). The Herball. Verified against its record · doi:10.5962/bhl.title.99400
- Grieve, M. (1931). A Modern Herbal, “Butterbur.” Book, not indexed
Verification
- Checked
- October 1, 2026
- Passes
- Every sentence read against its sources, in the pass over the remaining 343 entries
- The Standing line checked against the authority it names (EMA, WHO, FDA, CITES, Commission E)
- Every dated or regulatory claim checked by category across the database
- The mechanism read against ChEMBL (ChEMBL 37): curated mechanisms and measured activity
- Sources
- 3 cited: 2 verified against its record, 1 book, not indexed. 1 with the abstract on file.
- Corrections
- None were needed.
What was checked, how, and what was found is set out on the Verification page. A checked source is one whose record was found; it does not make the entry medical advice.
Cite This Entry
Version 1 · first published September 30, 2026
- Chicago
“Butterbur.” In Materia Medica, edited by B. C. P. Statema. Version 1. The Thinking Press, 2026–. Last modified September 30, 2026. https://thethinkingpress.org/materia-medica/butterbur.
- MLA
“Butterbur.” Materia Medica, edited by B. C. P. Statema, version 1, The Thinking Press, 30 Sept. 2026, thethinkingpress.org/materia-medica/butterbur. Accessed 8 Oct. 2026.
- APA
Butterbur. (2026, September 30). In B. C. P. Statema (Ed.), Materia medica (Version 1). The Thinking Press. Retrieved October 8, 2026, from https://thethinkingpress.org/materia-medica/butterbur
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See Also
Poisoned alike: pyrrolizidine alkaloids (veno-occlusive disease)
Coltsfoot · Borage · Comfrey · Alkanet · Houndstongue · Ragwort · the syndrome, with all of them →
Drawing on the same sources: Gerard, Grieve
Caesar’s mushroom · Woody nightshade · Caraway broth · Burdock · Cardamom · the bibliography →
Nearby in the alphabet
Calamine (Zinc carbonate and zinc oxide) · Bryony (Bryonia dioica (now Bryonia cretica subsp) · Camphor (The crystalline gum of Cinnamomum camphora) · Brown roll-rim (of birch woods) · Cantharides (The dried blister beetle Lytta vesicatoria) · Broom (Spartium junceum, or common broom, Cytisus scoparius)
Historical description, not medical advice.