Oregon Grape Root Benefits, Precautions and Tea Preparation

Oregon Grape Root Benefits, Precautions and Tea Preparation
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Oregon Grape

Oregon grape, Mahonia aquifolium, is a small evergreen ornamental shrub that is native to Oregon, Washington, northern California, northern Idaho and British Columbia. It is the state flower of Oregon. This beautiful plant has dark green leaves that take on a purplish color during the winter, bright yellow flowers with a honey-like fragrance that bloom in April to early May, and purple blue berries that grow in small clusters when ripe. Despite its name, these purple clusters are not grapes. It is the roots, yellow in color, that are used for medicinal purposes.

Oregon grape, a member of the Berberidaceae family, is a cousin of goldenseal, Hydrastis canadensis, and shares similar properties. In fact, Oregon grape has become a useful substitute for goldenseal, which was listed as an endangered species in 1991 due to overharvesting. The roots of both plants contain berberine, a bitter-tasting plant alkaloid that has been used medicinally in both Chinese and Ayurvedic medicine for many years. Berberine has been extensively studied and has been shown to have significant antimicrobial activity against bacteria, viruses, fungi and parasitic worms. Below are Oregon grape root benefits, as well as precautions and preparations, including directions for making Oregon grape tea.


Oregon grape root is often used as an herbal remedy for infections due to its antimicrobial activities. It is also used to improve liver and digestive function, treating symptoms such as reduced appetite, abdominal distension, stomach cramps, nausea and infectious diarrhea. According to the Encyclopedia of Natural Medicine, berberine is effective against diarrheas caused by E.coli, Salmonella paratyphi, Shigella dysenteriae, B. Klebsiella, Giardia lamblia, Entamoeba histolytica and Vibrio cholerae. In addition, it may help people who suffer from arthritis, gout and rheumatism.

Many studies have demonstrated positive results using Oregon grape to treat skin conditions, especially psoriasis. According to clinical trials, symptoms disappeared or improved in 81 percent of 443 people with psoriasis.[1]


When used appropriately, Oregon grape root is generally considered safe. If taken in high doses, it can cause diarrhea, shortness of breath and flu-like symptoms. It should be limited to short-term use only. Do not use it on a daily basis for more than seven days at a time. Wait at least one week before using it again. This will allow “good” bacteria in the intestine to recover. Oregon grape may decrease blood sugar levels and lower blood pressure so it should be used cautiously if you are diabetic or have hypotension. Anyone with a medical condition or taking medications should consult their health care provider before using. Women who are pregnant should avoid taking because it may cause contractions and miscarriage. It should also be avoided if breastfeeding.


You can buy creams, capsules and tinctures. Use as directed.

To prepare a cup of Oregon grape tea, pour 1 cup of boiling water over 1 teaspoon of dried root, cover and steep for 10 to 15 minutes. To experience the most Oregon grape root benefits, drink three cups a day. The taste is quite bitter, so you may want to add some cinnamon or orange peels.


[1] Muller, K., K. Ziereis, and I. Gawlik. 1995. The antipsoriatic Mahonia aquifolium and its active constituents: II. Antiproliferative activity against cell growth of human keratinocytes. Planta Medica 61(1): 74-75.

Michael Murray, N.D. and Joseph Pizzorno, N.D. “Encyclopedia of Natural Medicine” Prima Publishing 1998

Discovery Health: https://health.howstuffworks.com/wellness/natural-medicine/herbal-remedies/oregon-grape-herbal-remedies.htm

Photo by Trygve Berg / Flickr


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