Fool’s webcap
Cortinarius orellanus
- Known today as
- A tawny webcap of European woods.
- Kind
- Fungus
- Constituents
- orellanine
- Poisoning
- Orellanine poisoning
- In other databases
- GBIF search · Wikidata search
Revised October 3, 2026: Checked against its sources, each read in full, in part, or in its abstract. Version 1, first published September 25, 2026.
Deadly. Historical description only.
Fool’s webcap: what was it used for?
None.
Fool’s webcap: what does modern science say?
The same slow kidney poison as the deadly webcap.
Fool’s webcap: is it poisonous?
Yes, and it can kill. Its poisoning is orellanine poisoning: Two to twenty days: the longest latency of any mushroom poison, so the meal is seldom remembered. Historical description, not medical advice; in a poisoning, call a poison centre.
Pharmacognosy & Toxicology
- Constituents
- Mechanism
- As the deadly webcap.
- Toxic dose
- Not established; the kidney failure comes days after the meal (a median of 8.5 days in one review of cases).
- Syndrome
- Orellanine poisoning
- Standing
- None. Its relative the deadly webcap (C. rubellus) poisoned three people near Inverness in 1979 and the author of The Horse Whisperer in 2008.
- Danel, V. C., et al. (2001). Toxicon 39. Abstract read · the text read
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.
Fool’s webcap: what lore surrounds it?
A mass poisoning in Poland in the 1950s first revealed how dangerous it is, and orellanine was later isolated from it.
Sources
- Danel, V. C., Saviuc, P. F., & Garon, D. (2001). Main features of Cortinarius spp. poisoning: a literature review. Toxicon 39: 1053–1060. Abstract read · the text read
- Wikipedia contributors. “Orellanine.” Wikipedia, The Free Encyclopedia. en.wikipedia.org/wiki/Orellanine (read 2 October 2026). Read in full · the text read
- Wikipedia contributors. “Cortinarius rubellus.” Wikipedia, The Free Encyclopedia. en.wikipedia.org/wiki/Cortinarius_rubellus (read 2 October 2026). Read in full · the text read
Verification
- Checked
- October 1, 2026, and October 3, 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
- Every source read, in full, in part, or in its abstract, and every sentence checked against what was read (October 3, 2026)
- Sources
- 4 cited: 2 read in full, 2 abstract read. 2 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 25, 2026 · last revised October 3, 2026
- Chicago
“Fool’s webcap.” In Materia Medica, edited by B. C. P. Statema. Version 1. The Thinking Press, 2026–. Last modified October 3, 2026. https://thethinkingpress.org/materia-medica/fools-webcap.
- MLA
“Fool’s webcap.” Materia Medica, edited by B. C. P. Statema, version 1, The Thinking Press, 3 Oct. 2026, thethinkingpress.org/materia-medica/fools-webcap. Accessed 8 Oct. 2026.
- APA
Fool’s webcap. (2026, October 3). In B. C. P. Statema (Ed.), Materia medica (Version 1). The Thinking Press. Retrieved October 8, 2026, from https://thethinkingpress.org/materia-medica/fools-webcap
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See Also
Poisoned alike: orellanine poisoning
Nearby in the alphabet
Foxglove (Digitalis purpurea) · Foetid pills · Fox’s heart (The dried heart of a fox) · Fly agaric (white-spotted toadstool of fairy tales, of birch and pine woods) · Frankincense (The resin of Boswellia sacra and related trees) · The fig hand (made as a gesture or carved as a charm) · Friar’s balsam (storax, balsam of tolu, and aloes, in spirit) · Fig (Ficus carica)
Historical description, not medical advice.