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Drugs and Health Products

Monograph: Blessed Thistle - Oral

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Date: 2018-10-29


Cnicus benedictus (Germplasm Resources Information Network Taxonomy)

Proper Name(s)

Cnicus benedictus ( USDA 2008 )

Common Name(s)

Source Material

Herb top ( Williamson 2003 , Bradley 1992 )

Route Of Administration


Dosage Form(s)

Those suited to the allowable route(s) of administration. This monograph is not intended to include food-like dosage forms such as bars, chewing gums or beverages.

Use(s) or Purpose(s)

Statement(s) to the effect of:

  • Traditionally used in Herbal Medicine as a digestive tonic and bitter to increase appetite and aid digestion (stomachic).
  • Traditionally used in Herbal Medicine to help relieve indigestion (dyspepsia).
  • Traditionally used in Herbal Medicine as an expectorant to help relieve cold symptoms such as excessive mucus build up (excessive catarrh).
  • Traditionally used in Herbal Medicine as a digestive tonic and bitter to increase appetite, aid digestion (stomachic) and help relieve indigestion (dyspepsia).



Dose(s): 1 Day per day

See Appendix 1 for examples of appropriate dosage preparations and frequencies of use, according to cited references. The purpose of Appendix 1 is to provide guidance to industry.

Duration of use

No statement is required

Risk Information

Statement(s) to the effect of:

Caution(s) and Warning(s):
  • Consult a health care practitioner/health care provider/health care professional/doctor/ physician if symptoms persist or worsen.
  • Consult a health care practitioner/health care provider/health care professional/doctor/ physician prior to use if you are breastfeeding.

Do not use this product if you are pregnant.

Known Adverse Reaction(s):
Stop use if hypersensitivity/allergy occurs.

Non-medicinal ingredients

Must be chosen from the current Natural Health Products Ingredients Database and must meet the limitations outlined in the database.


  • The finished product specifications must be established in accordance with the requirements described in the NHPD Quality of Natural Health Products Guide.
  • The medicinal ingredient must comply with the requirements outlined in the Natural Health Products Ingredient Database (NHPID).

References cited

  • Blumenthal M, Goldberg A, Brinckmann J, editors. Herbal Medicine: Expanded Commission E Monographs. Boston (MA): Integrative Medicine Communications; 2000.
  • Bradley PR, editor. 1992. British Herbal Compendium: A Handbook of Scientific Information on Widely Used Plant Drugs, Volume 1. Bournemouth (GB): British Herbal Medicine Association.
  • Brinker F. 2001. Herb Contraindications and Drug Interactions, 3rd edition. Sandy (OR): Eclectic Medical Publications.
  • Felter HW, Lloyd JU. King's American Dispensatory, Volume 1, 18th edition. Sandy (OR): Eclectic Medical Publications; 1983 [Reprint of 1898 original].
  • McGuffin M, Hobbs C, Upton R, Goldberg A, editors. 1997. American Herbal Products Association's Botanical Safety Handbook. Boca Raton (FL): CRC Press.
  • McGuffin M, Kartesz JT, Leung AY, Tucker AO, editors. 2000. Herbs of Commerce, 2nd edition. Austin(TX): American Herbal Products Association.
  • USDA 2008: ARS, National Genetic Resources Program. Germplasm Resources Information Network (GRIN). National Germplasm Resources Laboratory, Beltsville (MD). [Accessed 2008-01-21]. Available at
  • Williamson EM. Potter's Herbal Cyclopaedia: The Authoritative Reference work on Plants with a Known Medical Use. Saffron Walden (UK): The C.W. Daniel Company Limited; 2003.
  • Wren RC. 1907. Potter's Cyclopedia of Botanical Drugs and Preparations. London (GB): Potter and Clark.

References reviewed

  • BHP 1983: British Herbal Pharmacopoeia. Cowling (GB): British Herbal Medical Association; 1983.
  • Blumenthal M, Busse W, Goldberg A, Gruenwald J, Hall T, Riggins C, Rister R, editors. The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. Austin (TX): American Botanical Council; 1998.
  • Bruneton J. Pharmacognosie, Phytochimie, Plantes Médicinales, 3rd edition. Paris (FR): Technique & Documentation; 1999.
  • Fauci AS, Braunwald E, Isselbacher KJ, Wilson JD, Martin JB, Kasper DI, Hauser SL and Longo DL, editors. Harrison's Principles of Internal Medicine, 14th edition. Toronto (ON): McGraw-Hill Health Professions Division; 1998.
  • Felter HW. The Eclectic Materia Medica, Pharmacology and Therapeutics. Sandy (OR): Eclectic Medical Publications; 1983 [Reprint of 1922 original].
  • Hoffmann D. 2003. Medical Herbalism: The Science and Practice of Herbal Medicine. Rochester (VT): Healing Arts Press.
  • Meyer JE. The Herbalist. Glenwood (IL): Meyerbooks; 1993.
  • Meyrick W. The New Family Herbal; or, Domestic Physician: enumerating, with accurate descriptions, all the known vegetables which are any way remarkable for medical efficacy; with an account of their virtues in the several diseases incident to the human frame. Birmingham (UK): Knott and Lloyd; 1790.
  • Pugh MB, editor. Stedman's 27th Medical Dictionary. New York (NY): Lippincott Williams & Wilkins; 2000.
  • Wiersema J, León B. 1999. World Economic Plants: A Standard Reference. Boca Raton (FL): CRC Press LLC.
  • Williamson EM, Evans FJ, Wren RC. Potter's New Cyclopaedia of Botanical Drugs and Preparations. Saffron Walden (GB): C.W. Daniel Company Limited; 1988.

Appendix 1: Examples of appropriate dosage preparations, frequencies of use and directions for use


Dried aerial parts:

  • 4 - 6 g, per day (Blumenthal et al. 2000)
  • 0.6 - 4 g (10 - 60 grains), per day (Felter and Lloyd 1983 [1898])


1.5 - 2 g dried aerial parts, 3 times per day (Blumenthal et al. 2000; Bradley 1992)

Directions for use:

Pour 150 ml of boiling water on dried aerial parts and infuse (Blumenthal et al. 2000)

Fluid extract:

1.5 - 2 g dried equivalent, 3 times per day (1:1, 25% ethanol, 1.5 - 2 ml) (Blumenthal et al. 2000; Bradley 1992)


  • 1.5 - 2 g dried equivalent, 3 times per day (1:5, 7.5 - 10 ml) (Blumenthal et al. 2000)
  • 0.6 - 1.2 g dried equivalent, 3 times per day (1:5, 25% ethanol, 3 - 6 ml) (Bradley 1992)