Natural Products

Goldenseal

Hydrastis canadensis

Efficacy

• Indications with proven efficacy:
  None
• Indications with proof that it is not effective:
  Adulterant in drug screens
• Also used for these other indications, but with no proof of efficacy:
  Acne (topically)
  Anorexia
  Cancer
  Canker sores (topically)
  Conjunctivitis (topically, eyewash)
  Dyspepsia with hepatic symptoms
  Gastritis, colitis and peptic ulcers
  Hemorrhage
  Hemorrhoids
  Itching and eczema(topically)
  Malaria
  Mucosal tonic
  Nasal congestion and inflammation of the respiratory tract
  Sore gums (mouth-wash)
  Tinnitus
  Urinary and digestive tract infections
  Wounds (topically)

Security

• Risk of Drug Interactions: Moderate
• Adverse Effects: Not Frequent

What is it?

Goldenseal is a perennial herb commonly found on the American continent. It is considered as an endangered plant because of overharvesting for medicinal use. The root (rhizome) is the medicinal part of the plant. It contains alkaloids, such as hydrastine and berberine, which are believed to have medicinal properties. The herb is believed to have antimicrobial, immunostimulant, anticonvulsant, sedative, uterotonic, choleretic and vasoconstrictive properties. The herb's alkaloids are poorly absorbed when taken orally.

Warning

In 2004, Canada adopted new regulations that control the manufacturing, packaging, labeling and importing of natural health products. The new regulations also include an adverse reaction reporting system. Products that conform to the regulation's criteria are identified with a natural product number (NPN) or homeopathic medicine number (DIN-HM) and can be legally sold in Canada. This number indicates that the product meets specific criteria for safety and purity, not that it is effective for any indication.

Medicinal plants content varies naturally from plant to plant – just as fruits from the same package may vary in taste and texture. There is no standard to measure the active content of each plant. Thus, efficacy of natural products should be expected to vary from brand to brand as well as from bottle to bottle of the same brand.

For more information about the Natural Health Products Regulations, or to check if a product has been assessed, visit the Health Canada website at http://www.hc-sc.gc.ca/dhp-mps/prodnatur/index-eng.php.

Does it work?

There are no recognized indications for the use of goldenseal. Nonetheless, it is used to regularize some medical conditions, even though its actual usefulness remains to be determines. While there is insufficient reliable information to conclude that it is effective in any indication, certain "doses" are commonly recommended:

• Usual oral dose:
  0.5 to 1 gram of dried rhizome 3 times a day. A tea can also be prepared by simmering 0.5 to 1 gram of dried rhizome in 150 ml of boiling water for 5 to 10 minutes.
• Mouthwash:
  Steep 6 grams of dried herb in 150 ml of boiling water for 5 to 10 minutes. Strain and allow to cool.

Is it safe?

• When used appropriately, goldenseal dos not appear to cause any serious toxicity. Taking small doses (usual doses) is probably safe for most people. It may however cause mucosal irritation. People should avoid large doses and prolonged use. Large doses can be toxic in several regards: throat and mouth irritation, nausea, vomiting, diarrhea, tingling sensation in the extremities. There were also reports of stimulant activity, respiratory failure, elevated arterial pressure and seizures.
• Goldenseal is a uterine stimulant that can affect menstruation and induce uterine contractions. Pregnant women and those who wish to become pregnant should avoid this product. Because berberine is secreted in breast milk, lactating women should not use goldenseal.
• Goldenseal is contraindicated in presence of jaundice. Berberine could increase bilirubin levels and exacerbate the disease.
• Large doses of goldenseal appear to decrease the effect of anticoagulants. Before taking goldenseal, check with your pharmacist to make sure that there are no interactions with your regular medication.

Clinical notes

• Goldenseal is a highly popular herb, but very few scientific data exist to support its use. Even though large doses may be toxic, usual doses rarely cause adverse effects.

References

1. Natural Medicines Comprehensive Database, Therapeutic Research Faculty, 2007
2. Facts and Comparisons, The Lawrence review of Natural Products, 2000
3. Lexi-comp, Natural Therapeutics Pocket Guide, 2000-2001
4. Barnes J. et Al. Herbal Medicines, 2nd edition, Pharmaceutical Press, 2002
5. Pierce Andrea, Practical Guide to Natural Medicines, 1999
6. Passeportsanté.net. Hydraste du Canada. http://www.passeportsante.net
7. Rotblatt M. et Ziment I. Evidence-Based Herbal Medicine, Hanley & Belfus, 2002