Astragalus: benefits, dosage, contraindications

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Astragalus is a perennial plant that belongs to the Fabaceae family (beans, fava beans), native from northern and eastern China to Mongolia. It is a very large genus comprising more than 2,000 species. The main medicinal species according to the Chinese Pharmacopoeia are Astragalus membranaceus and Astragalus mongholicus. Astragalus generally grows to about 40 cm tall but can reach up to 120 cm. Yellowish flowers appear in summer along a dense spike. Astragalus is used in Chinese medicine for its tonic and adaptogenic properties. It strengthens energy, the spleen and the stomach, and raises the Yang Qi. In herbal medicine, the dried roots are used. Astragalus contains a variety of active components, including more than 40 saponins, such as astragalosides whose major constituents are: Astragaloside IV and its aglycone derivative the cycloastragenol, and Astragalosides I - III, which are acetylated astragalosides. Astragalus also contains several flavonoids, notably isoflavones, polysaccharides, numerous trace elements, amino acids and coumarins. Astragalus is traditionally used in TCM (traditional Chinese medicine) for respiratory allergies, diabetes, kidney diseases, as well as for strengthening and regulating the immune system. It is considered an adaptogen and is recommended for cases of stress and fatigue. Astragalus is also used for liver protection and for the fight against viruses and bacteria. It is also used as an adjunct in cancer treatments.

Other name(s) 

Radix Astragali, Huang Qi

Scientific name(s)

Astragalus propinquus, Astragalus membranaceus, Astragalus mongholicus

Family or group: 

Plants

Active ingredients:

Flavonoids

Polysaccharides

Cycloastragenol


Indications

Scoring methodology

EFSA approval.

Several randomized, double-blind, controlled clinical trials (> 2), including a significant number of patients (>100), with consistently positive conclusions for the indication.
Several randomized, double-blind, controlled clinical trials (> 2), including a significant number of patients (>100), with positive conclusions for the indication.
One or more randomized studies, or several cohorts or epidemiological studies, with positive conclusions for the indication.
Clinical studies exist but are uncontrolled, with conclusions that may be positive or conflicting.
No clinical studies to date that can demonstrate the indication.


Allergic rhinitis
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Clinical studies show that taking a specific astragalus root extract containing 40% polysaccharides at a dose of 160 mg orally twice a day for 3 to 6 weeks improves symptoms such as nasal discharge, sneezing, and itching, compared to placebo, in adults with seasonal allergic rhinitis.nn

Posologie

posologieOral: root

posologie320 mg

duration6 weeks

populationAdults

formulationstandardized extract


Congestive heart failure
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Clinical research suggests that taking 2.25 to 7.5 grams of astragalus orally, twice daily for 14 to 30 days, in combination with conventional treatment for congestive heart failure, improves cardiac function, left ventricular ejection fraction, and walking distance compared with conventional treatment alone.

Posologie

posologieOral: root

posologie2.25 - 7.5 g

duration30 - days

populationAdults

formulationpowder


Type 2 diabetes
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A clinical study shows that astragalus, administered as a daily intravenous injection or orally for up to 4 months, modestly improves fasting and postprandial blood glucose levels compared with a control group in patients with type 2 diabetes.

Posologie

posologieOral: root

posologie40 - 60 g

duration4 - months

populationAdults

formulationaqueous decoction


Renal insufficiency
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Numerous studies have been conducted in humans on chronic kidney disease. Some have demonstrated an improvement in proteinuria, serum albumin, and hemoglobin. In individuals with diabetic nephropathy, protection of renal function has been observed. Clinical research shows that the use of Astragalus together with conventional treatment can improve creatinine clearance, hemoglobin levels, and serum creatinine compared with conventional treatment alone in patients with chronic kidney disease.

Posologie

posologieOral: root

posologie3 - 120 g

duration1 - month

populationAdults

formulationpowder


Stroke
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A preclinical study shows that taking astragalus extracts after a stroke improves cognitive and social functioning compared with placebo. Another study showed that oral administration of 3 g of astragalus (Astragalus Radix) three times a day (total of 9 g), starting after the onset of a stroke for 14 days, resulted in faster neural recovery with improvement in functional ability and memory.

Posologie

posologieBy mouth: root

posologie9 g

duration2 - weeks

populationAdults

formulationpowder


Lung cancer
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Analyses of clinical research results suggest that taking herbal products containing astragalus may increase the effectiveness of platinum-based chemotherapy or radiotherapy for advanced non-small-cell lung cancer. Taking herbal products containing astragalus appears to reduce the risk of death by 33% at one year, by 33% at two years, and by 24% at three years compared with controls. However, because most of the studies included in the meta-analyses were of poor quality, further reliable studies are needed to confirm these findings.

Posologie

posologieBy mouth: root

posologie2 g

populationAdults

formulationpowder


Cold
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Oral administration of an Astragalus extract to 1,000 people reduced the incidence or shortened the duration of the common cold. Indeed, an increase in IgA and IgG levels was observed in the patients' nasal secretion.

Posologie

posologieOral: root

posologie2 g

formulationdry extract


Immune support
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In a small study, it was shown that 1.23 g of Astragalus membranaceus administered as a mother tincture in two divided doses per day for 7 days activated the immune system (technically, the number of immune cells expressing CD4, CD8 and CD69 increased after 7 days of supplementation; the CD4 and CD8 cells included T cells). The authors conclude that astragalus was more effective than echinacea. Traditionally, astragalus is used for winter viral illnesses and conditions associated with decreased immunity.

Posologie

posologieOral: root

posologie1.23 g

formulationmother tincture


Chemotherapy
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A meta-analysis of 19 clinical trials conducted in adults with cervical cancer receiving chemotherapy shows that the use of Chinese medicinal herbs containing astragalus increases tumor response and reduces chemotherapy-associated adverse effects compared with chemotherapy alone. Another 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 together with conventional chemotherapy reduces the risk of anemia by 51% compared with chemotherapy alone.

Posologie

posologieOral: root

posologie2 g

formulationpowder


Diabetic nephropathy
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A meta-analysis of small, low-quality clinical studies involving more than 4,700 patients shows that adding intravenous astragalus to routine treatment for 2 to 12 weeks modestly improves blood urea nitrogen, serum creatinine, creatinine clearance, urinary proteins, urinary albumin, and serum albumin compared with routine treatment alone in patients with diabetic nephropathy. Another meta-analysis of preliminary clinical research findings suggests that taking products containing astragalus for up to 10 months modestly improves visual acuity and fundus findings compared with control in patients with diabetic retinopathy.

Posologie

posologieOral: root

posologie2 g

formulationpowder


Diabetic retinopathy
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A meta-analysis of small, low-quality clinical studies involving more than 4,700 patients shows that adding intravenous astragalus to routine treatment for 2 to 12 weeks modestly improves blood urea nitrogen, serum creatinine, creatinine clearance, urinary protein, urinary albumin, and serum albumin compared with routine treatment alone in patients with diabetic nephropathy. Another meta-analysis of preliminary clinical research results suggests that taking astragalus-containing products for up to 10 months modestly improves visual acuity and fundus findings compared with control in patients with diabetic retinopathy.

Posologie

posologieOral: root

posologie2 g

formulationpowder


Gastric cancer
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A meta-analysis of 35 randomized controlled trials involving 2,670 patients with advanced gastric cancer shows that taking traditional Chinese medicines containing astragalus, intravenously or orally, in combination with platinum-based chemotherapy, may improve the objective response rate, disease control rate, one-year survival rate, and quality of life, and may also reduce the severity of chemotherapy-associated adverse effects, compared with chemotherapy alone. nn

Posologie

posologieOral: root

posologie2 g

formulationpowder


Fatigue
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A preliminary clinical study conducted in adults with chronic fatigue syndrome shows that taking a 200 ml decoction containing 30 g of astragalus, 30 g of kudzu, 10 g of turmeric along with other herbs, in two divided doses per day for 3 months, improves fatigue symptoms compared with baseline. nnAnother preliminary clinical study shows that taking 1.5 g of a product containing 66% extracts of astragalus and red sage in a 1:1 ratio twice a day for 4 weeks improves fatigue intensity compared with placebo.nn

Posologie

posologieOral: root

posologie2 g

formulationpowder


Properties


Immunomodulator

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Astragalus appears to enhance the immune response. In laboratory studies, astragalus has been observed to activate certain types of immune cells, such as B cells and macrophages. Astragalus also increases the production of certain immune substances, such as interferon and IgA and IgG antibodies, which help fight infections. Astragalus also appears to boost the activity of natural killer cells and other types of T cells, which are important for defense against disease, as shown by a small clinical study conducted on male professional rowers.

Usages associés

Allergic rhinitis, Immune support

Nephroprotective

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Laboratory research suggests that astragalus may improve renal microvascular lesions by increasing blood flow and enhancing the kidney's filtration process and endothelial cell function. Astragaloside IV may reduce renal fibrosis (thickening and scarring of kidney tissues) by decreasing inflammation, due to its action on certain biochemical pathways in the body, both in laboratory studies and in vivo in animals.

Usages associés

Renal insufficiency, Diabetic nephropathy

Antiviral

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Astragalus and its components have shown antiviral properties against several viruses, including those that affect both humans and animals (such as cytomegalovirus, hepatitis B virus, herpes, and certain adenoviruses). Research has specifically examined its effect on Coxsackie B virus, which can cause myocarditis. These studies indicate that astragalus may inhibit the replication of this virus and improve immune cell profiles. The antiviral effect of astragalus may be due both to inhibition of viral entry into cells and to stimulation of the immune response.

Usages associés

Common cold

Anti-inflammatory

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In many in vitro and in vivo models of inflammation, astragalus root extracts and their constituents have demonstrated an anti-inflammatory effect. This effect occurs through inhibition of the transcription factor NFκB (nuclear factor-kappa B: a protein of the transcription factor superfamily involved in the immune response and the response to cellular stress), which controls the expression of genes involved in the cellular and molecular inflammatory response.

Usages associés

Allergic rhinitis

Antioxidant

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Different constituents of astragalus have shown antioxidant properties in vitro and in vivo. Indeed, the isoflavonoids formononetin, calycosin and a glycosylated derivative are able to scavenge free radicals and inhibit lipid peroxidation. Astragaloside IV reduces the production of free radicals and lipid peroxidation and increases the antioxidant defenses of liver cells.

Usages associés

Stroke

Anticancer

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In traditional Chinese medicine, astragalus root is used in cancer management. Indeed, astragalus in extract form is able to increase the percentage of lymphocytes. Polysaccharides increase the production of cytokines involved in the anti-tumor response (TNF-α and IFN-γ). Astragaloside IV is also able to regulate the levels of immune cells.

Usages associés

Lung cancer, Chemotherapy, Gastric cancer

Hypoglycemic

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Astragalus polysaccharides improve muscle insulin sensitivity by partially restoring the insulin signaling pathway and helping the translocation of the glucose transporter GLUT-4.nnHuman and laboratory research suggests that astragalus may also contribute to protection against the formation of advanced glycation end products, which are harmful to health.nn

Usages associés

Type 2 diabetes

Cardiovascular

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Astragalus flavonoids reduce serum total cholesterol and LDL cholesterol concentrations, and increase HDL cholesterol. Preservation of cardiac function may be related to the antioxidant effect and improved cell survival.nn

Usages associés

Congestive heart failure, Stroke


Safe dosage

Adult: 9 g - 30 g

Dosage:nn- Dry root decoction: 10 to 15 g, up to 30 g per daynn- Powder: 2 to 10 g per day.nnOral doses of astragalus up to 30 g/day have been used without reported adverse effects during 4 months of treatment.nn


Interactions

Médicaments

Cyclophosphamide: moderate interaction

Research findings regarding the effect of astragalus on cyclophosphamide-induced immunosuppression are contradictory.

Immunosuppressant: moderate interaction

Astragalus appears to stimulate immune function. Theoretically, taking astragalus may reduce the effects of immunosuppressive therapy. Immunosuppressive medications that may be affected include: azathioprine, cyclosporine, daclizumab, mycophenolate (CellCept), prednisone, and other corticosteroids...

Lithium: moderate interaction

Astragalus may reduce urinary excretion of lithium, which can increase lithium levels.

Plantes ou autres actifs

Astragalus: strong interaction

Some species of astragalus contain high levels of selenium; concurrent use may cause selenium toxicity.


Precautions

Lactating women: avoid

Avoid due to lack of information on precautions to follow for lactating women.nn

Autoimmune diseases: use with caution

Theoretically, astragalus could exacerbate certain autoimmune diseases by stimulating disease activity. It should be used with caution in patients with autoimmune conditions such as multiple sclerosis, systemic lupus erythematosus, rheumatoid arthritis, or others.nn


Contraindications

Pregnancy: contraindicated

According to studies, astragaloside, a constituent of astragalus, has a toxic effect on the mother and her fetus. Do not consume during pregnancy.nn

Children up to 12 years old: contraindicated

Contraindicated in children under 12 years of age.nn