Astragalus

Preliminary clinical research shows that taking a specific astragalus root extract standardized to contain 40% polysaccharides (Lectranal, Milsing d.o.o.) 160 mg orally twice daily for 3-6 weeks improves symptoms such as rhinorrhea, sneezing, and itching when compared with placebo in adults with seasonal allergic rhinitis (17355).

One preliminary clinical study shows that taking a liquid decoction containing astragalus 30 grams, dong quai 30 grams, zizyphus 10 fruits, horny goat weed 15 grams, dodder 30 grams, and three slices of ginger, daily in two divided doses for 3 months, can increase menstrual frequency when compared to baseline in patients with amenorrhea (33050). The validity of this finding is limited by the lack of a comparator group. Additionally, it is unclear if this effect is due to astragalus, other ingredients, or the combination.

A preliminary clinical trial shows that taking astragalus 20 grams orally three times daily for 2 weeks can improve cardiac output, but not diastolic function, when compared to baseline in patients with angina (33063). The validity of these findings is limited by the lack of a comparator group.

A large unblinded clinical study in patients with breast cancer or lymphoma receiving a chemotherapy regimen containing epirubicin shows that intravenous use of astragalus 500 mg daily for 14 days during 2 courses of chemotherapy modestly attenuates the decline in left ventricular ejection fraction (LVEF) and reduces the occurrence of cardiotoxicity when compared with standard care (110479). However, this study was conducted in China, which limits the generalizability of its results.

Preliminary clinical research in patients 15 years and older with chronic aplastic anemia shows that giving intravenous astragalus in combination with stanozolol 2 mg three times daily produces greater improvements in symptoms and blood cell counts than stanozolol alone. Astragalus was given as 80-120 grams daily for repeated 15-day courses at 7-10 day intervals for at least 4 months (32840).

Preliminary clinical research in children with mild asthma shows that taking a combination of astragalus, cordyceps, Radix stemonae (Bai Bu), bulbus fritillariae cirrhosae, and Baikal skullcap orally for 6 months does not improve asthma symptoms, measures of lung function, or total steroid use when compared with placebo (32935).

A meta-analysis of 19 clinical trials in adults with cervical cancer who are receiving chemotherapy shows that the use of Chinese herbal medicines containing astragalus increases tumor response (complete and partial responses) and Karnofsky performance score and reduces chemotherapy-associated adverse effects when compared with chemotherapy alone (107479). However, most studies included in the meta-analysis were low-quality, and all studies were conducted in China. Higher quality studies in other geographic locations are needed to confirm these findings. Additionally, it is unclear if any effects are due to astragalus, other ingredients, or the combination.

A meta-analysis of low-quality clinical trials in patients with colorectal cancer shows that oral or intravenous use of traditional Chinese medicine therapies containing astragalus and other ingredients along with conventional chemotherapy reduces the risk of anemia by 51% when compared with chemotherapy alone (102099). It is unclear if these effects are due to astragalus, the other ingredients, or the combination.

One preliminary clinical study shows that intravenous infusion of astragalus 40 grams in 250 mL of solution, given daily for 21 days during each of four courses of chemotherapy, reduces diarrhea by 59% when compared to chemotherapy alone (32747). Additionally, a meta-analysis of low-quality clinical trials in patients with colorectal cancer shows that oral or intravenous use of traditional Chinese medicine therapies containing astragalus and other ingredients along with conventional chemotherapy reduces the risk of diarrhea by 45% when compared with chemotherapy alone (102099). It is unclear if these effects are due to astragalus, the other ingredients, or the combination.

A meta-analysis of low-quality clinical trials in patients with colorectal cancer shows that oral or intravenous use of traditional Chinese medicine therapies containing astragalus and other ingredients along with conventional chemotherapy reduces the risk of thrombocytopenia by 41% when compared with chemotherapy alone (102099). It is unclear if these effects are due to astragalus, the other ingredients, or the combination.

A meta-analysis of low-quality clinical research in Chinese patients with advanced non-small cell lung cancer shows that intravenous infusion of astragalus along with platinum-based chemotherapy reduces the risk of vomiting by 38% when compared with platinum-based chemotherapy alone (100698). Another preliminary clinical study shows that intravenous infusion of astragalus 40 grams in 250 mL of solution, given daily for 21 days during each of four courses of chemotherapy, reduces nausea by 36% and vomiting by 50% when compared with chemotherapy alone (32747). Higher quality studies are needed to confirm these results.

The use of astragalus in combination with other ingredients for prevention of CINV has also been investigated. A meta-analysis of low-quality clinical trials in patients with colorectal cancer shows that oral or intravenous use of traditional Chinese medicine therapies containing astragalus and other ingredients along with conventional chemotherapy reduces the risk of nausea and vomiting by 44% when compared with chemotherapy alone (102099). It is unclear if these effects are due to astragalus, the other ingredients, or the combination.

A meta-analysis of low-quality clinical trials in patients with colorectal cancer shows that oral or intravenous use of traditional Chinese medicine therapies containing astragalus and other ingredients along with conventional chemotherapy does not reduce the risk of nephrotoxicity when compared with chemotherapy alone (102099). The effects of astragalus when used alone are unclear.

One clinical study in patients with advanced cancer shows that treatment with an intravenous infusion of a partially purified astragalus extract (PG2, Pharmagenesis), 500 mg three times weekly for 4 weeks during chemotherapy, improves fatigue scores after one week, but not after two and four weeks, when compared with placebo (33034).

One preliminary clinical study in adults with CFS shows that taking a 200 mL decoction containing astragalus 30 grams, kudzu 30 grams, codonopsis 15 grams, red sage 10 grams, aizoon stonecrop 15 grams, horny goat weed 10 grams, turmeric 10 grams, and calamus 10 grams, in two divided doses daily for 3 months improves fatigue symptoms when compared to baseline (32920). Another preliminary clinical study shows that taking 1.5 grams of a specific product (Myelophil, Samik Pharmaceutical Company) containing 66% of extracts of astragalus and danshen in a 1:1 ratio twice daily for 4 weeks improves fatigue severity when compared with placebo. However, taking 3 grams of the same product twice daily does not seem to have a benefit (32883). It is unclear if these effects are due to astragalus, the other ingredients, or the combination.

A meta-analysis of preliminary clinical research in patients with CKD shows that using astragalus, usually as an injection, along with conventional treatment modestly improves creatinine clearance by 6 mL/min, serum creatinine by 0.25 mg/dL, and hemoglobin levels by 1 gram/dL when compared with conventional treatment alone (90660). However, the studies included in the meta-analysis were of low quality. Additionally, a moderate-sized clinical study in patients with CKD and type 2 diabetes shows that taking astragalus 15 grams daily for 5 days per week in combination with standard care for 48 weeks ameliorates the decline in glomerular filtration rate, but does not improve the urinary albumin to creatinine ratio, when compared with standard care alone (114803). The validity of these findings is limited by methodological flaws, including inadequate blinding. Also, it is not known if astragalus reduces mortality or attenuates the progression to kidney failure.

A meta-analysis of low-quality clinical studies in adults with COPD shows that intravenous astragalus 10-60 mL (concentration not specified) once or twice daily for 2 weeks in combination with ambroxol hydrochloride and other conventional therapies improves COPD clinical symptoms, some measures of pulmonary function, and arterial blood gases when compared with conventional therapies alone (114688). All studies were conducted in China which may limit generalizability of the results. It is unclear if these effects are due to astragalus, ambroxol hydrochloride, or the combination.

A meta-analysis of results from low-quality clinical studies shows that intravenous injection of a combination of astragalus and danshen for up to 90 days might decrease fibrosis when compared with control in patients with liver cirrhosis (90662). However, it is unclear if this is due to astragalus, danshen, or the combination.

A meta-analysis of clinical trials in patients with colorectal cancer shows that oral or intravenous use of traditional Chinese medicine therapies containing astragalus and other ingredients along with conventional chemotherapy improves quality of life scores and increases the rate of tumor response by 52% when compared with chemotherapy alone (102099). It is unclear if these effects are due to astragalus, the other ingredients, or the combination.

A meta-analysis of preliminary clinical research in Chinese patients with type 2 diabetes shows that astragalus, given as a daily intravenous injection 40-80 grams or taken orally 40-60 grams daily as an aqueous decoction for up to 4 months, modestly improves fasting and postprandial blood glucose levels when compared to a control group. Oral astragalus seems to improve these outcomes slightly more than intravenous astragalus. Orally, astragalus also seems to improve fasting insulin levels and insulin resistance, although its effect on glycated hemoglobin (HbA1c) is inconsistent. (95909). Astragalus has also been evaluated as an adjuvant therapy to metformin. A meta-analysis of several mostly small clinical studies in adults with type 2 diabetes shows that taking astragalus 10-50 grams daily with metformin modestly reduces fasting blood glucose by approximately 12 mg/dL, 2-hour postprandial blood glucose by 12 mg/dL, and HbA1c by 0.9% when compared with metformin monotherapy (112809). A meta-analysis of mostly low-quality clinical studies in patients with diabetes shows that taking astragalus in the form of traditional Chinese medicine, with or without Western medicine, reduces fasting blood glucose, 2-hour postprandial glucose, and glycated hemoglobin when compared with Western medicine alone (114805). However, the clinical studies included in both of these meta-analyses are of low methodological quality and include only Chinese patients, which limits the reliability and generalizability of the results.

Some research has evaluated astragalus in combination with other ingredients. One preliminary clinical study in adults with previously untreated type 2 diabetes shows that taking astragalus 210 mg, goldthread 350 mg, and honeysuckle 840 mg three times daily before meals for 3 months does not improve fasting blood glucose, postprandial blood glucose, or HbA1c when compared with placebo, although glucose disposal rate is modestly improved (32925).

Meta-analyses of small, low-quality clinical studies including over 4700 patients shows that adding intravenous astragalus to routine therapy for 2-12 weeks modestly improves blood urea nitrogen, serum creatinine, creatinine clearance, urinary protein, urinary albumin, and serum albumin when compared with routine therapy alone in patients with diabetic nephropathy (33019, 102100).

A meta-analysis of mostly low-quality clinical studies in patients with diabetic neuropathy shows that taking astragalus in the form of traditional Chinese medicine, with or without Western medicine, modestly reduces signs and symptoms of diabetic neuropathy when compared with Western medicine alone (114805). However, this improvement may not be clinically significant. Additionally, all studies were conducted in China which may limit generalizability of the results.

A meta-analysis of results from preliminary clinical research suggests that taking astragalus-containing products for up to 10 months modestly improves visual acuity and fundus manifestations when compared with control in patients with diabetic retinopathy. However, the included studies had methodological limitations, and the results were heterogeneous (90655).

A meta-analysis of 35 randomized, controlled trials involving 2670 patients with advanced gastric cancer shows that taking either intravenous or oral traditional Chinese medicines containing astragalus in conjunction with platinum-based chemotherapy may improve objective response rate, disease control rate, 1-year survival rate, and quality of life, and may also reduce the severity of chemotherapy-associated adverse effects, when compared with chemotherapy alone (107480). The validity of this meta-analysis is limited by potential publication bias, unclear randomization methods, and substantial heterogeneity among the included studies. Additionally, it is unclear if these effects are due to astragalus, other ingredients, or the combination.

Preliminary clinical research shows that injecting 0.5 mL/kg of solution containing astragalus 2 grams/mL daily for 10 days improves hearing in people with sudden deafness or acute acoustic trauma when compared with a control group (33028, 33033).

A meta-analysis of small to moderate-sized low quality clinical studies in adults with heart failure with reduced ejection fraction (HFrEF) shows that oral astragalus 30 grams twice daily or intravenous astragalus 20-60 mL (concentration not specified) daily for 2-4 weeks combined with conventional treatment modestly increases left ventricular ejection fraction (LVEF), decreases brain natriuretic peptide levels, and increases 6-minute walking distance when compared with conventional treatment alone (114804). Findings are limited by significant heterogeneity. Additionally, all studies were conducted in China which may limit generalizability of the results.

The conflicting nature of these results are reflected in other small studies. One preliminary clinical study in adults with CHF shows that intravenous infusion of astragalus 60 grams daily for 20 days improves LVEF and left ventricular end-diastolic volume (LVEDV) when compared with conventional treatment (32755). However, another preliminary clinical study shows that intravenous astragalus 60 grams daily for 28 days in combination with conventional treatment for CHF does not improve LVEF, LVEDV, or left ventricular end-systolic volume when compared with conventional treatment alone (32812). Other preliminary clinical research shows that taking oral astragalus 2.25-7.5 grams twice daily for 14-30 days in combination with conventional treatment improves cardiac function, LVEF, and walking distance when compared with conventional treatment alone (33018, 33022). However, each of these studies has methodological problems.

One small clinical study shows that taking a combination containing mainly Baikal skullcap root, glossy privet fruit, astragalus root, and Eupolyphaga et polyphage (Ailing granules) 20 grams twice daily for 4 months improves HIV/AIDS symptoms and CD4 cell counts (32824). However, taking a different combination containing licorice, yin chen, white mulberry, astragalus, and safflower orally for 12 weeks is associated with only a slight decline in viral load and no change in CD4 cell counts (32795). The effects of astragalus alone are unclear.

One meta-analysis in patients with advanced NSCLC shows that intravenous administration of astragalus along with platinum-based chemotherapy increases the rate of one-year survival by 40% when compared with platinum-based chemotherapy alone (100698). Other meta-analyses in these patients show that use of oral or intravenous astragalus-containing herbal products appears to reduce the risk of death at six months by 42%, at one year by 33%, at two years by 27% to 33%, and at three years by 15% to 24% when compared with platinum-based chemotherapy or radiotherapy alone (15001, 90656). Additionally, a network meta-analysis of clinical research in patients with NSCLC ranks intravenous administration of astragalus along with a combination of docetaxel and cisplatin as the most effective of various Chinese herbal medicine injection and docetaxel and cisplatin combinations (114689). However, most studies included in the meta-analyses were low-quality, and all studies were conducted in China. Higher quality studies in other geographic locations are needed to confirm these findings.

A meta-analysis of 48 small, low-quality clinical studies in adults with idiopathic membranous nephropathy conducted in China shows that taking astragalus 20-90 grams per day in combination with a variety of other supplements, in addition to conventional therapy, modestly improves the rate of complete or partial renal remission when compared with conventional therapy (e.g. angiotensin-converting enzyme inhibitors, immunosuppression). Adding astragalus combinations to conventional therapy also modestly reduces proteinuria and serum creatinine (112010). However, the interpretation of these findings is limited by the heterogeneity of the included studies and variable definitions of complete and partial renal remission. Additionally, it is unclear if these effects are due to astragalus, other ingredients, or the combination.

One preliminary clinical study shows that taking Dang Gui Buxue Tang, an herbal decoction containing astragalus and dong quai extract, 3 grams daily for 6 months does not reduce the incidence of menopausal hot flashes (32857). However, another preliminary clinical study shows that taking Dang Gui Buxue Tang 3-6 grams daily for 12 weeks reduces hot flash frequency by up to 40% and night sweat frequency up to 53% when compared to baseline (90659). Each 1.5 grams of Dang gui Buxue Tang contains extract prepared from dong quai 1.5 grams and astragalus 7.5 grams (90659). Another small clinical study in females with moderate or severe menopausal symptoms shows that taking a tablet containing astragalus and Rubus coreanus extract 1000 mg twice daily for 12 weeks modestly improves symptom and quality of life scores when compared with placebo (110478). However, the validity of these findings is limited by a high rate of study participant discontinuation.

A meta-analysis of 13 mostly small, low-quality clinical studies in adults and children with viral myocarditis shows that astragalus injection may improve the total effective rate and reduce markers of inflammation when compared with conventional treatment (110477). However, most studies included in the meta-analysis were low-quality, dosing was variable, and all studies were conducted in China. Higher quality studies in other geographic locations are needed to confirm these findings. Several clinical studies report improvements in cardiac enzymes, cardiac function, or viral load in peripheral leukocytes with the use of astragalus preparations, but results are inconsistent and the methodological quality of these studies is low (33084, 33105, 33217, 33218, 33220, 33221, 33223). Doses demonstrating benefit include intramuscular astragalus extract, equivalent to 8 grams daily for 3-4 months (33105) and intravenous astragalus extract 40 grams daily for 2 weeks (33218, 33221). It is unclear if astragalus speeds recovery or reduces the risk of mortality due to myocarditis.

A meta-analysis of results from two preliminary clinical studies shows that taking astragalus 7.5-15 grams twice daily for 3-6 months reduces the risk of infection by 38% when compared to control in children with nephrotic syndrome (33036).

Preliminary clinical research shows that taking a combination of astragalus, rhubarb, turmeric, red sage root, ginger, and gallic acid concurrently with a reduced-calorie diet does not improve weight loss when compared with a reduced-calorie diet alone in adults who are overweight or obese (20347).

A preliminary clinical study shows that taking astragalus extract (Sun Ten Pharmaceutical Co. Ltd.) 2.8 grams three times daily for 28 days improves fatigue and some quality of life measures such as social functioning, role functioning, and physical functioning, when compared with placebo in patients experiencing fatigue following a recent stroke (95908).

A preliminary clinical study in adults with lupus nephritis shows that intravenous infusions of astragalus 40 grams daily for 12 consecutive days monthly for 3 months, in combination with corticosteroids and cyclophosphamide once monthly as an intravenous drip, can improve symptoms, reduce infections, and reduce urinary protein excretion when compared to treatment with corticosteroids and cyclophosphamide alone (32838).

Preliminary clinical research shows that injecting 0.5 mL/kg of solution containing astragalus 2 grams/mL daily for 10 days reduces tinnitus in patients with acute acoustic trauma when compared to a control group (33028).

A moderate-size clinical study in females aged 18-45 with uncomplicated UTIs shows that taking a supplement containing astragalus root extract 100 mg, d-mannose, citric acid, dandelion, and prebiotics as a sachet dissolved in water twice daily for 5 days improves complete resolution of UTI symptoms and clearance of bacteriuria at days 6 and 35 when compared with placebo (111757). However, it is unclear if these effects are due to astragalus, other ingredients, or the combination.

Theoretically, astragalus might exacerbate certain autoimmune diseases by stimulating disease activity; avoid use or use with caution in patients with autoimmune diseases such as multiple sclerosis, systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), or others. Astragalus seems to stimulate immune function (303, 423, 3713, 10777).