Woodlouse
Millepedae, sows, slaters
- Known today as
- Woodlice, the small crustaceans of damp places under rocks and logs, called millepedes in the old pharmacopoeias.
- Kind
- Animal, in 1 older authority
- Constituents
- calcium carbonate, chitin, haemocyanin
- Earliest authority here
- Pliny (AD 23/24–79)
Revised October 3, 2026: An older authority added from a text read in full. Checked against its sources, each read in full, in part, or in its abstract. Version 1, first published September 30, 2026.
Woodlouse: what was it used for?
For jaundice, obstructions of the kidneys and urinary passages, and rheum falling on the eyes: dried in white wine and powdered, or steeped alive in white wine as the wine of hog-lice.
Woodlouse: what does modern science say?
Kept now as pets by children and by invertebrate collectors.
Pharmacognosy & Toxicology
- Constituents
- calcium carbonate ChEMBLthe cuticle
- chitin
- haemocyanin
- Mechanism
- The woodlouse is a crustacean whose cuticle is chitin-protein fibrils with calcium carbonate. Quincy held it diuretic and cleansing, from a nitrous salt it was thought to draw from its food.
- Toxic dose
- Quincy gave the prepared powder from ten grains to two scruples.
- Standing
- In the London Pharmacopoeia of 1721 and in Quincy’s dispensatory of 1718.
- Quincy, J. (1718). Pharmacopoeia Officinalis et Extemporanea, “Millepedes.” Read in part · the text read
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.
Woodlouse: what lore surrounds it?
Prepared millepedes stayed in the London Pharmacopoeia into the eighteenth century.
Woodlouse: what did the older authorities say?
- Pliny
- Pliny's multipedes are the creatures “belonging to the earth-worm genus, hairy, with numerous feet, forming curves as they crawl, and contracting themselves when touched: the Greeks give to this insect the name of ‘oniscos,’ others, again, that of ‘tylos.’” The rolling-up is the woodlouse's signature, and the remedy is for the ears: “Boiled with leek-juice in a pomegranate rind, it is highly efficacious, they say, for pains in the ears; oil of roses being added to the preparation, and the mixture injected into the ear opposite to the one affected.”
Sources
- Pharmacopoeia Londinensis (1721). Read in part · the text read
- Pomet, P. (1694). Histoire générale des drogues (English, A Compleat History of Druggs, 1712). Read in part · the text read
- Pliny the Elder, Natural History 29.39, trans. J. Bostock & H. T. Riley (1855), Perseus Digital Library. Read in part · the text read
- Wikipedia, “Woodlouse.” Read in full · the text read
- Seidl, B., et al. (2021). The dorsal tergite cuticle of Helleria brevicornis: ultrastructure, mineral distribution, calcite microstructure and texture. Journal of Structural Biology: X 5. Abstract read · the text read
- Jemec Kokalj, A., et al. (2023). Proteomics of the haemolymph of the terrestrial crustacean Porcellio scaber reveals components of its innate immunity under baseline conditions. Biochimie. Abstract read · 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
- Each quotation from the older authorities checked word for word against the text, read in full
- Every source read, in full, in part, or in its abstract, and every sentence checked against what was read (October 3, 2026)
- Sources
- 7 cited: 1 read in full, 4 read in part, 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 30, 2026 · last revised October 3, 2026
- Chicago
“Woodlouse.” 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/woodlouse.
- MLA
“Woodlouse.” Materia Medica, edited by B. C. P. Statema, version 1, The Thinking Press, 3 Oct. 2026, thethinkingpress.org/materia-medica/woodlouse. Accessed 8 Oct. 2026.
- APA
Woodlouse. (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/woodlouse
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See Also
Sharing calcium carbonate, chitin, haemocyanin
Corallium rubrum · Vine ash · Crabs’ eyes · Pearls, prepared · Cuttlefish bone · Snail
Also in Pliny the Elder
Yarrow in Pliny the Elder · Wood sorrel in Pliny the Elder · Yellow dock in Pliny the Elder · Woad in Pliny the Elder · everything Pliny the Elder names →
Drawing on the same sources: Pomet, Wikipedia, Quincy
Zedoary · Turmeric · Balsam of Peru · Yew · Adder’s-tongue fern · Oil of bricks · the bibliography →
Nearby in the alphabet
Woody nightshade · Wormwood, oil of (Artemisia absinthium) · Witches’ butter (Black or yellow jelly fungi that swell on dead branches after rain) · Witch marks (Symbols scratched or burned near doors and fireplaces)
Historical description, not medical advice.