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Drugs and Health Products

Monograph: Thuja - Oral

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Date: 2008-04-25

NHPID Name

Thuja occidentalis (USDA 2008)

Proper Name(s)

Thuja occidentalis L. (Cupressaceae) ( USDA 2008 )

Common Name(s)

Thuja ( McGuffin et al. 2000 )

Source Material

Herb top ( BHP 1983 , Felter and Lloyd 1983[1898] )

Route Of Administration

Oral

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 an expectorant to help relieve bronchial catarrh  (Hoffmann 2003, Williamson 2003, BHP 1983, Felter and Lloyd 1983[1898])

Dose(s)

Adults:

Preparation: Dry, Powder, Decoction & Infusion + All Non-Standardised Extracts

Dose(s): 1 - 2 Grams 3 times per day, dried herb tops

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

For occasional use only  (Brinker 2001, McGuffin et al. 1997)

Risk Information

Statement(s) to the effect of:

Caution(s) and Warning(s):
  • Consult a health care practitioner if symptoms persist.
  • Consult a health care practitioner if symptoms worsen.
  • Consult a health care practitioner prior to use if you are breastfeeding  (Brinker 2010)
  • Consult a health care practitioner prior to use if you are taking other herbs containing thujone (e.g. wormwood, sage, tansy, and juniper)  (Rietjens et al. 2005, Hoffmann 2003)

Contraindication(s):
Do not use if you are pregnant  (Hoffmann 2003, Brinker 2001, BHP 1983)

Known Adverse Reaction(s):
No statement is required

Non-medicinal ingredients

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

Specifications

  • 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

  • Berardi RR, DeSimone EM, Newton GD, Oszko MA, Popovich NG, Rollins CJ, Shimp LA, Tietze KJ, editors. Handbook of Nonprescription Drugs: An Interactive Approach to Self-Care, 13th edition. Washington (DC): American Pharmaceutical Association; 2002.
  • BHP 1983: British Herbal Pharmacopoeia. Cowling (GB): British Herbal Medical Association; 1983.
  • Brinker F. 2001. Herb Contraindications and Drug Interactions, 3rd edition. Sandy (OR): Eclectic Medical Publications.
  • Brinker F. 2010. Online Updates and Additions to Herb Contraindications and Drug Interactions, 3rd edition. Sandy (OR): Eclectic Medical Publications. [Updated 2010 July 13; Accessed 2013 January 30]. Available from: http://www.eclecticherb.com/emp/updatesHCDI.html
  • Felter HW, Lloyd JU. 1983. King's American Dispensatory, Volume 2, 18th edition. Sandy (OR): Eclectic Medical Publications [Reprint of 1898 original].
  • Hoffmann D. 2003. Medical Herbalism: The Science and Practice of Herbal Medicine. Rochester (VT): Healing Arts Press.
  • 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.
  • Rietjens IM, Martena MJ, Boersma MG, Spiegelenberg W, Alink GM. Molecular mechanisms of toxicity of important food-borne phytotoxins. Molecular Nutrition & Food Research 2005;49(2):131-158.
  • USDA 2008: ARS, National Genetic Resources Program. Germplasm Resources Information Network (GRIN). National Germplasm Resources Laboratory, Beltsville (MD). [Accessed 2008-01-21]. Available at http://www.ars-grin.gov/cgi-bin/npgs/html/tax_search.pl
  • 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.

References reviewed

  • Burkhard PR, Burkhardt K, Haenggeli CA, Landis T. Plant-induced seizures: reappearance of an old problem. Journal of Neurology 1999;246(8):667-670.
  • EC-SCF 2003: European Commission Scientific Committee on Food. Opinion of the Scientific Committee on Thujone. Brussels (B): European Commission Health and Consumer Protection Directorate-General. Scientific Committee on Food. Scientific Committee on Thujone; February 6, 2003, pp. 1-11. [Accessed 2008-04-25]. Available at: www.ec.europa.eu/food/fs/sc/scf/out162_en.pdf
  • EEC 1988: European Economic Committee. Council Directive 88/388/EEC on the approximation of the laws of the Member States relating to flavourings for use in foodstuffs and to source materials for their production. Brussels (B): European Economic Committee Council Directive 88/388/EEC of 22 June 1988. [Accessed 2008-04-25]. Available at: ec.europa.eu/food/fs/sfp/addit_flavor/flav09_en.pdf
  • Stafstrom CE. Seizures in a 7-month-old child after exposure to the essential plant oil thuja. Pediatric Neurology 2007;37(6):446-448.

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

ORAL:

Dried aerial parts:

1 - 2 g, 3 times per day (Williamson 2003; BHP 1983)

Infusion:

1 - 2 g dried aerial parts, 3 times per day (Williamson 2003; BHP 1983)

Directions for use:

Pour 250 ml of boiling water over dried aerial parts and steep for 10-15 minutes (Hoffmann 2003).