Horseradish
Mountain radish, great raifort, red cole; French moutarde des Allemands; Gerard’s Raphanus rusticanus; Cochlearia armoracia L., now Armoracia rusticana
- Known today as
- Armoracia rusticana, of the family Cruciferae, long cultivated and of obscure origin; Grieve reports that some authorities think it native to eastern Europe, from the Caspian through Russia and Poland to Finland. The fresh root is the drug. Unbroken it has no smell; scraped or bruised it gives off its pungent oil, because the glucoside sinigrin and the enzyme myrosin that splits it lie in separate cells and meet only when the cells are crushed, producing allyl isothiocyanate, the same oil as black mustard’s. Boiling makes it vapid and inert.
- Kind
- Plant, in 1 older authority
- Constituents
- sinigrin, myrosin, allyl isothiocyanate
- Earliest authority here
- Gerard (1597) and Parkinson (1640), as Grieve quotes them (A Modern Herbal, 1931)
- In other databases
- Plants of the World Online · GBIF · Wikidata
Caution. Grieve notes that taken too freely it is emetic, and that its oil is so pungent that a drop scents a room; as a poultice it acts like a mustard plaster. None of the sources read for this entry reports on its safety as a medicine taken alone.
Horseradish: what was it used for?
A stimulant and diuretic, and a sauce. Grieve calls it stimulant, aperient, rubefacient, diuretic, and antiseptic: with oily fish or rich meat “a spur to complete digestion,” a strong diuretic used in stone and dropsy, laid on as a poultice instead of a mustard plaster for rheumatism and chilblains, and made into a syrup for hoarseness and a remedy for worms in children.
Horseradish: what does modern science say?
No European monograph for the root alone was found for this entry. In modern trials it appears in combination: a German phase III trial published in 2026 gave women with recurrent cystitis a combination of nasturtium herb and horseradish root or placebo for six months, and found the risk of recurrence reduced by about a third, with no more adverse effects than placebo. That result belongs to the combination, not to horseradish alone.
Pharmacognosy & Toxicology
- Constituents
- sinigrina glucoside, split by the enzyme myrosin when the cells are crushed
- myrosinthe enzyme, held in separate cells
- allyl isothiocyanate ChEMBLthe pungent volatile oil, the same as black mustard’s
- Mechanism
- The volatile oil does not exist in the unbroken root; it forms only when scraping or bruising brings sinigrin and myrosin together.
- Standing
- There is no European monograph for the root alone. A 2026 phase III trial tested it only in combination with nasturtium herb.
- Grieve, M. A Modern Herbal, “Horseradish.” As published on botanical.com. Read in full · the text read
- Albrecht U, et al. (2026). Clinical evaluation of the efficacy and safety of nasturtium herb and horseradish root versus placebo in the continuous prophylaxis of recurrent uncomplicated cystitis: a double-blind randomised clinical trial. BMC complementary medicine and therapies. PMID 41782129. 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.
Horseradish: what lore surrounds it?
Gerard used it to illustrate the old doctrine of antipathies: “Divers thinke that this Horse Radish is an enimie to Vines,” so that a vine planted near it “bendeth backward from it as not willing to have fellowship with it.” Folkard records that it is said to be one of the five “bitter herbs” of the Mishna eaten at Passover, with coriander, horehound, lettuce, and nettle, and that it is under Mars. Grieve explains that ‘horse’ in its name means coarse, to distinguish it from the edible radish, as in horse-mint and horse chestnut.
Horseradish: what did the older authorities say?
- Gerard (1597) and Parkinson (1640), as Grieve quotes them
- In Gerard’s day the English still knew it as a drug: he reported that “the Horse Radish stamped with a little vinegar put thereto, is commonly used among the Germans for sauce to eate fish with,” as the English used mustard. By 1640 Parkinson found it eaten in England too, “but, as I said, it is too strong for tender and gentle stomaches.” Its old French name, the Germans’ mustard, records the same borrowing.
Sources
- Grieve, M. A Modern Herbal, “Horseradish.” As published on botanical.com. Read in full · the text read
- Folkard, R. (1884). Plant Lore, Legends, and Lyrics, “HORSERADISH.” Project Gutenberg, 44638. Read in part · the text read
- Albrecht U, et al. (2026). Clinical evaluation of the efficacy and safety of nasturtium herb and horseradish root versus placebo in the continuous prophylaxis of recurrent uncomplicated cystitis: a double-blind randomised clinical trial. BMC complementary medicine and therapies. PMID 41782129. Abstract read · the text read
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
- Sources
- 3 cited: 1 read in full, 1 read in part, 1 abstract read. 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.
Club members can point at a technical term in this entry, such as a constituent, an action, or a word of Jung’s, to read its definition from the source. The Club.
Cite This Entry
Version 1 · first published October 17, 2026
- Chicago
“Horseradish.” In Materia Medica, edited by B. C. P. Statema. Version 1. The Thinking Press, 2026–. Last modified October 17, 2026. https://thethinkingpress.org/materia-medica/horseradish.
- MLA
“Horseradish.” Materia Medica, edited by B. C. P. Statema, version 1, The Thinking Press, 17 Oct. 2026, thethinkingpress.org/materia-medica/horseradish. Accessed 17 Oct. 2026.
- APA
Horseradish. (2026, October 17). In B. C. P. Statema (Ed.), Materia medica (Version 1). The Thinking Press. Retrieved October 17, 2026, from https://thethinkingpress.org/materia-medica/horseradish
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See Also
Sharing sinigrin, allyl isothiocyanate
Brassica napus · Sisymbrium officinale · Capsella bursa-pastoris
Also in M. Grieve
Laburnum in M. Grieve · Horse chestnut in M. Grieve · Lime flower in M. Grieve · Guelder rose in M. Grieve · everything M. Grieve names →
Drawing on the same sources: Grieve, Folkard
Horsetail · Houndstongue · Labdanum · Lesser bean-trefoil · the bibliography →
Nearby in the alphabet
Horehound (Marrubium vulgare) · Houseleek (Sempervivum tectorum) · Hop (Humulus lupulus) · Human fat (Fat rendered from the bodies of the executed) · Honeyed wine and honeyed water (Wine or water sweetened with honey)
Historical description, not medical advice.
