Blackberries grow in wet areas across the United States and Europe. Several species of blackberry exist: Rubus fructicosus is the most common European species and Rubus canadensis is a common North American species. While the leaves are used most frequently for medicinal preparations, the root is sometimes used as well.
Historical or traditional use (may or may not be supported by scientific studies): Since ancient Greek physicians prescribed blackberry for gout, the leaves, roots, and even berries have been used as herbal medicines.1 The most common uses were for treating diarrhea, sore throats, and wounds. These are similar to the uses of its close cousin, the red raspberry (Rubus idaeus), and a somewhat more distant relative, the blueberry (Vaccinium corymbosum).
Active constituents: The presence of large amounts of tannins give blackberry leaves and roots an astringent effect that may be useful for treating diarrhea.2 These same constituents may also be helpful for soothing sore throats.
How much is usually taken? The German Commission E monograph recommends 4.5 grams of blackberry leaf per day.3 Blackberry tea is prepared by adding 1.5 grams of leaves or powdered root to 250 ml of boiling water and allowing it to steep for 10 to 15 minutes. Three cups per day should be drunk. Alternatively, one may use 3�4 ml of tincture three times each day.
Are there any side effects or interactions? Tannins can cause nausea and even vomiting in people with sensitive stomachs. People with chronic gastrointestinal problems might be particularly at risk for such reactions. Taking blackberry leaf or root preparations with food may reduce risk of gastrointestinal problems in some people.
At the time of writing, there were no well-known drug interactions with blackberry.
1. Castleman M. The Healing Herbs. New York: Bantam Books, 1991, 106�10.
2. Tyler V. Herbs of Choice: The Therapeutic Use of Phytomedicinals. New York: Pharmaceutical Products Press, 1994, 53.
3. 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, 91.