# Soapwort (Saponaria officinalis) *Soaproot, bouncing Bet, latherwort, fuller’s herb, bruisewort, sopewort, crow soap, sweet Betty, wild sweet William; Greek *strouthion*; Latin *radix*, *herba lanaria*; *Saponaria officinalis* L.* **Known today as.** *Saponaria officinalis*, of the family Caryophyllaceae, a stout perennial of central and southern Europe, grown in English gardens, with smooth lance-shaped leaves and loose clusters of large pink flowers, often double, from July to September. The root and leaves are the drug. Grieve gives saponin as the chief constituent of the root, and notes its taste: bitter and slightly sweet, then a persistent pungency and a numbness in the mouth. Kind: Plant > **Caution.** Grieve warned that it “should be very cautiously used owing to its saponin content,” and Dioscorides that it could cause abortion. None of the sources read for this entry reports on its safety in modern use. ## What was it used for? A washing plant first and a medicine second. Dioscorides knew it as the herb “which fullers use for cleaning their wool.” As a medicine Grieve records a decoction for the itch, and the plant as tonic, diaphoretic, and alterative, used in jaundice, rheumatism, skin complaints, and “old venereal complaints,” especially where mercury had failed; it is also sternutatory, provoking sneezing. ## What does modern science say? No European monograph covers it, and the searches of Europe PMC made for this entry found no clinical trial of it as a medicine. Its saponins are now laboratory material: a 2026 study isolated new saponins from the root and found that one of them strongly increased the killing power of saporin, a protein toxin, against breast-cancer cells in culture, as a way of carrying protein drugs into cells. ## Pharmacognosy and toxicology - **saponin**: the chief constituent of the root **Mechanism.** In a 2026 laboratory study one of its saponins strongly increased the toxicity of the protein toxin saporin to breast-cancer cells in culture. **Standing.** There is no European monograph, and no clinical trial of it as a medicine was found for this entry. ## What did the older authorities say? **Dioscorides, *De materia medica* (1st century), book 2.** Dioscorides calls the root sharp and diuretic, and gives it with honey for disorders of the liver, coughs, and asthma, with other roots to break and pass stones and soften a hard spleen, and as a plaster for leprosy; it induced sneezing, and put up into the nostrils with honey it purged through the mouth. He adds that applied below it brings on menstruation and is an abortifacient. The translators of the modern English version identify his *strouthion* as soapwort. **Culpeper, *The Complete Herbal* (1653).** Under “Sopewort, or Bruisewort,” a plant of Venus, Culpeper records that country people bruised the leaves and laid them on cut fingers, hands, or legs to heal them, and that some boasted of it as a diuretic for stone and dropsy and extolled it as an absolute cure of the French pox, better than sarsaparilla or guaiacum; “which, how true it is, I leave others to judge.” ## Sources - Grieve, M. *A Modern Herbal*, “Soapwort.” As published on botanical.com. - Dioscorides. *De materia medica*, 2-193, in the modern English version of T. A. Osbaldeston and R. P. A. Wood (Johannesburg: Ibidis, 2000), after Goodyer’s translation of 1655. Internet Archive. - Culpeper, N. *The Complete Herbal*, “SOPEWORT, OR BRUISEWORT.” Project Gutenberg, 49513. - Lim-Paik C, et al. (2026). Improving Cytotoxicity of Saporin with Saponin SO1406 Isolated from the Roots of Saponaria Officinalis. *Biomedicines*. PMID 41898273. - Grieve, M. *A Modern Herbal*, “Soapwort.” As published on botanical.com. - Lim-Paik C, et al. (2026). Improving Cytotoxicity of Saporin with Saponin SO1406 Isolated from the Roots of Saponaria Officinalis. *Biomedicines*. PMID 41898273. --- *Soapwort.* In *Materia Medica*, edited by B. C. P. Statema. Version 1, revised 2026-10-17. The Thinking Press. https://thethinkingpress.org/materia-medica/soapwort Historical description, not medical advice.