Coumadin -- the trade name for the drug warfarin -- is an anticoagulant used to prevent blood clots. Your doctor may prescribe Coumadin if you have a pulmonary embolism or thrombophlebitis; it is also used to prevent heart attack or stroke. Coumadin can cause abnormal bleeding; in serious cases, hemorrhage can result. If you experience reddish or dark urine, black, tarry stools, nosebleed or bleeding gums, alert your physician immediately. Many substances -- including the herb astragalus -- can interact with Coumadin. Don't begin any herbal or supplementary regimen while taking Coumadin without talking to your doctor first.
Features
Astragalus -- botanically known as Astragalus membranaceus and also called milk vetches -- is a perennial herb native to northern China and presently cultivated in China, Korea and Japan. The fibrous root is sold in varying lengths for use in herbal remedies; it is also available dried and powdered in capsules. Astragalus is revered in traditional Chinese medicine, where it is known as huang chi. Traditional herbal uses of astragalus include treating diabetes and kidney disease. Astragalus is a primary component of Chinese Fu Zheng herbal therapy, intended to promote vigor and general well-being. Present-day herbalists advise the use of astragalus to boost the immune system of patients who have undergone chemotherapy.
Constituents and Effects
Astragalus contains saponins -- or natural soap-like substances -- as well as triterpene glycosides called astragalosides. Assorted polysaccharides, the compounds glucose, galactose and arabinose, and various amino acids are present in astragalus as well.
Drugs.com, which provides peer-reviewed medical information to consumers, reports that the saponins in astragalus can stimulate the growth of human lymphocytes, or white blood cells. The website also credits astragalus with liver-protective and antioxidant effects, as well as anti-inflammatory and blood pressure-lowering properties. Memorial Sloan-Kettering Cancer Center concurs that astragalus reduces immune suppression from chemotherapy and notes that it improves the responses of lymphocytes in both healthy subjects and cancer patients.
Research
In a meta-analysis published in 2006 in the "Journal of Clinical Oncology," the authors evaluated the results of randomized trials of astragalus that studied the herb's abilities to reduce the toxicity of chemotherapy used to treat lung cancer. They found that astragalus stimulated macrophage and natural killer cell activity, thus helping to normalize the immune system after platinum-based cancer treatments.
Interaction with Coumadin
University of Maryland Medical Center cautions that astragalus can intensify the effects of Coumadin, increasing the risk of bleeding. If you take Coumadin, you must consult your doctor before trying astragalus and only take it if your doctor tells you it is safe to do so. According to Drugs.com, the typical dosage for astragalus is from between 4 to 6 g a day of the powdered root. The use of astragalus hasn't been well studied in pregnancy; don't take astragalus if you are pregnant or breastfeeding.
References
- Drugs.com: Complete Astragalus Information
- People's Pharmacy; Warfarin Side Effects; Joe and Terry Graedon; September 2006
- "Journal of Clinical Oncology"; Astragalus-Based Chinese Herbs and Platinum-Based Chemotherapy For Advanced Non-Small-Cell Lung Cancer: Meta-Analysis of Randomized Trials; M. McCulloch, et al.; January 2006
- University of Maryland Medical Center: Possible Interactions With Astragalus; UMMC Staff; January 2007
- Memorial Sloan-Kettering Cancer Center: Astragalus; June 2010
