Nutritional Supplement

Oak

Also indexed as: Quercus spp.

Side Effects

Except for the occasional upset stomach or constipation reported after drinking the tea, oak bark is rarely associated with side effects. There are no known reasons to avoid oak during pregnancy or breast-feeding, though oak can cause constipation. It is safe for use in children and infants. The German Commission E monograph warns against people with open sores, wounds, high fever, orinfection bathing in water with oak bark.14

References

1. Weiss RF. Herbal Medicine. Beaconsfield, UK: Beaconsfield Publishers Ltd., 1988, 328-9.

2. Konig M, Scholz E, Hartmann R, et al. Ellagitannins and complex tannins from Quercus petraea bark. J Nat Prod 1994;57:1411-5.

3. Schilcher H. Phytotherapy in Paediatrics. Stuttgart, Germany: Medpharm Scientific Publishers, 1997, 49-50.

4. Weiss RF. Herbal Medicine. Gothenberg, Sweden: Ab Arcanum and Beaconsfield: Beaconsfield Publishers Ltd, 1988, 328-9.

5. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Foods, Drugs, and Cosmetics, 2d ed. New York: John Wiley & Sons, 1996, 168-70.

6. Ellingwood F. American Materia Medica, Therapeutics and Pharmacognosy. Sandy, OR: Eclectic Medical Publications, 1919, 1998, 354.

7. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Foods, Drugs, and Cosmetics, 2d ed. New York: John Wiley & Sons, 1996, 168-70.

8. Ellingwood F. American Materia Medica, Therapeutics and Pharmacognosy. Sandy, OR: Eclectic Medical Publications, 1919, 1998, 354.

9. Plein K, Burkard G, Hotz J. Treatment of chronic diarrhea in Crohn disease. A pilot study of the clinical effect of tannin albuminate and ethacridine lactate. Fortschr Med 1993;111:114-8 [in German].

10. Konig M, Scholz E, Hartmann R, et al. Ellagitannins and complex tannins from Quercus petraea bark. J Nat Prod 1994;57:1411-5.

11. Schilcher H. Phytotherapy in Paediatrics. Stuttgart, Germany: Medpharm Scientific Publishers, 1997, 49-50.

12. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Foods, Drugs, and Cosmetics, 2d ed. New York: John Wiley & Sons, 1996, 485-7.

13. Blumenthal M, Busse WR, Goldberg A, et al. (eds). The Complete Commission E Monographs: Therapeutic Guide to Herbal Medicines. Boston, MA: Integrative Medicine Communications, 1998, 175-6.

14. Blumenthal M, Busse WR, Goldberg A, et al. (eds). The Complete Commission E Monographs: Therapeutic Guide to Herbal Medicines. Boston, MA: Integrative Medicine Communications, 1998, 175-6.

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The information presented by TraceGains is for informational purposes only. It is based on scientific studies (human, animal, or in vitro), clinical experience, or traditional usage as cited in each article. The results reported may not necessarily occur in all individuals. For many of the conditions discussed, treatment with prescription or over the counter medication is also available. Consult your doctor, practitioner, and/or pharmacist for any health problem and before using any supplements or before making any changes in prescribed medications. Information expires December 2025.