Astragalus
Astragalus membranaceus; Astragalus mongholicus; Huang-qi; Milk-vetch root
Astragalus (Astragalus membranaceus) has been used in Traditional Chinese Medicine (TCM) for thousands of years. It was often combined with other herbs to strengthen the body against disease. Astragaus is called an adaptogen, meaning it helps protect the body against various stresses, including physical, mental, or emotional stress.
Astragalus may help protect the body from diseases such as cancer and diabetes. It contains antioxidants, which protect cells against damage. Astragalus is used to protect and support the immune system, preventing colds and upper respiratory infections, lowering blood pressure, treating diabetes, and protecting the liver.
Astragalus has antibacterial and anti-inflammatory properties. People sometimes use it on the skin for wound care. In addition, studies have shown that astragalus has antiviral properties and stimulates the immune system, suggesting that it may help prevent colds.
In the United States, researchers have looked at astragalus as a possible treatment for people whose immune systems have been weakened by chemotherapy or radiation. In these studies, astragalus supplements seem to help people recover faster and live longer. Research on using astragalus for people with AIDS has produced mixed results.
Recent research in China suggests that, because astragalus is an antioxidant, it may help people with severe forms of heart disease, relieving symptoms, lowering cholesterol levels, and improving heart function. At low-to-moderate doses, astragalus has few side effects. However, it does interact with a number of other herbs and prescription medications. Astragalus may also be a mild diuretic, meaning it helps rid the body of excess fluid.
Plant Description
Astragalus is a perennial plant, about 16 to 36 inches tall, that is native to the northern and eastern parts of China, as well as Mongolia and Korea. It has hairy stems with leaves made up of 12 to 18 pairs of leaflets. The root is the medicinal part of the plant, and is usually harvested from 4-year-old plants.
Parts Used
The dried root is used medicinally.
Medicinal Uses and Indications
Astragalus has been used for the following:
- Adaptogen. Protects the body from stress and disease.
- Anemia. One early study suggested astragalus may improve blood counts in people with aplastic anemia. The study was poorly designed, so more research is needed.
- Colds and influenza. In TCM, astragalus is used as part of an herbal combination to prevent or treat colds, although TCM theory holds that, in some cases, it may make colds worse. Evidence in animal and laboratory tests suggests it may act against viruses like the ones that cause colds.
- Diabetes. Astragalus appears to lower blood sugar. More studies are needed to determine whether it can help treat diabetes.
- Fatigue or lack of appetite from chemotherapy. Some studies suggest astragalus may help reduce side effects from chemotherapy. The studies have not been well designed, however. More research is needed.
- Heart disease. Several studies suggest that astragalus may act as an antioxidant and help treat heart disease. Other studies suggest astragalus may help lower cholesterol levels.
- Hepatitis. A few studies have used a combination of herbs containing astragalus to treat hepatitis. Results have been mixed.
- Kidney disease. Preliminary research suggests astragalus may help protect the kidneys and may help treat kidney disease. More studies are needed.
- Seasonal allergies. One study found that astragalus may help reduce symptoms in people who have allergic rhinitis or hayfever.
- Cancer. Preliminary studies suggest astragalus may have anti-tumor effects, specifically against melanoma and leukemia.
Available Forms
Astragalus root may be available in a variety of forms:
- Tincture (liquid alcohol extract)
- Capsules and tablets, standardized and non-standardized
- Injectable forms for use in hospital or clinical settings in Asian countries
- Topically for the skin
How to Take It
Pediatric
There is not a lot of scientific evidence about giving astragalus to children, so ask your doctor first. According to TCM, you should not give astragalus to a child with fever because the herb may make the fever last longer or grow stronger. Dosage should be determined by your doctor.
Adult
Dosage depends on condition being treated, age, and weight. Work with your physician to determine the safest and most effective dosage for you. Higher doses may suppress the immune system. For best results, use a standardized astragalus supplement. Dosages depend on a number of factors, such as whether astragalus is being used primarily as an adaptogen or for other reasons. People should work with a knowledgeable provider to determine the appropriate dosing schedule for their needs.
Precautions
At recommended doses, astragalus has no serious side effects and can generally be used safely. It does interact with other herbs and medications (see Possible Interactions section).
Evidence about whether astragalus is safe for women who are breastfeeding or nursing is lacking. Talk to your doctor before taking any medication, including herbs.
People with autoimmune disease should speak with their doctor first before taking Astagalus because it may stimulate the immune system.
Many practitioners recommend against using any single "adaptogenic" herbs over long periods of time. Instead, they might suggest rotating among several "adaptogens" every couple of months.
Possible Interactions
If you take any of the following medications, you should not use astragalus without first asking your doctor:
Drugs that suppress the immune system: Astragalus may interfere with these drugs. If you have an autoimmune disease, such as rheumatoid arthritis or lupus, or take cyclophosphamide, a medication used to reduce the chances of rejection in transplant recipients, or corticosteroids, do not take astragalus.
Lithium: Astragalus can make it harder for the body to get rid of lithium, so dangerously high levels of the drug could build up.
Supporting Research
Chen KT, Su CH, Hsin LH, et al. Reducing fatigue of athletes following oral administration of huangqi jianzhong tang. Acta Pharmacol Sin. 2002;23(8):757-761.
Cheng Y, Tang K, Wu S, et al. Astragalus polysaccharides lowers plasma cholesterol through mechanisms distinct from statins. PLoS One. 2011;6(11):e27437.
Duan P, Wang ZM. [Clinical study on effect of Astragalus in efficacy enhancing and toxicity reducing of chemotherapy in patients of malignant tumor]. Zhongguo Zhong Xi Yi Jie He Za Zhi. 2002;22(7):515-517.
Hao Y, Qiu QY, Wu J. Effect of Astragalus polysaccharides in promoting neutrophil-vascular endothelial cell adhesion and expression of related adhesive molecules. Zhongguo Zhong Xi Yi Jie He Za Zhi. 2004;24(5):427-430.
Hei ZQ, Zhang JJ, Lin SQ, et al. [Effects of Astragalus membranaceus injection on nitric oxide and endothelin concentration of intestinal mucosa after hemorrhage shock-reperfusion in rats]. Zhongguo Zhong Yao Za Zhi. 2004;29(5):444-447.
Huang XY, Zhang SZ, Wang WX. Enhanced antitumor efficacy with combined administration of astagalus and pterostilbene for melanoma. Asian Pac J Cancer Prev. 2014;15(3):1163-9.
Jia XH, Yin BH, Li JC. [Effect of astragalus injection on U937 leukemia cells proliferation and apoptosis and relevant molecular mechanisms]. Zhongguo Dang Dai Er Ke Za Zhi. 2013;15(12):1128-33.
Kim SH, Lee SE, Oh H, et al. The radioprotective effects of bu-zhong-yi-qi-tang: a prescription of traditional Chinesemedicine astragalus. J Chin Med. 2002;30(1):127-137.
Li M, Wang W, Xue J, Gu Y, Lin S. Meta-analysis of the clinical value of Astragalus membranaceus in diabetic nephropathy. J Ethnopharmacol. 2011;133(2):412-9.
Mao SP, Cheng KL, Zhou YF. [Modulatory effect of Astragalus membranaceus on Th1/Th2 cytokine in patients with herpes simplex keratitis]. Zhongguo Zhong Xi Yi Jie He Za Zhi. 2004;24(2):121-123.
Matkovic Z, Zivkovic V, Korica M, et al. Efficacy and safety of Astragalus membranaceus in the treatment of patients with seasonal allergic rhinitis. Phytother Res. 2010;24:175-81.
Shao BM, Xu W, Dai H, et al. A study on the immune receptors for polysaccharides from the roots of Astragalus membranaceus, a Chinese medicinal herb. Biochem Biophys Res Commun. 2004;320(4):1103-1111.
Shi FS, Yang ZG, Di GP. [Effect of Astragalus saponin on vascular endothelial cell and its function in burn patients]. Zhongguo Zhong Xi Yi Jie He Za Zhi. 2001;21(10):750-751.
Wang D, Zhuang Y, Tian Y, Thomas GN, Ying M, Tomlinson B. Study of the effects of total flavonoids of Astragalus on atherosclerosis formation and potential mechanisms. Oxid Med Cell Longrev. 2012;2012:282383.
Yang QY, Lu S, Sun HR. Clinical effect of Astragalus granule of different dosages on quality of life in patients with chronic heart failure. Chin J Integr Med. 2011;17(2):146-9.
Zhang HW, Lin ZX, Xu C, Leung C, Chan LS. Astragalus (a traditional Chines medicine) for treating chronic kidney disease. Cochrane Database Syst Rev. 2014;10:CD008369.