Astralagus root extract
Also known as: Astragalus mongholicus, Astragalus root, Huang Qi, Astragalus membranaceus
Overview
Astragalus root extract is derived from the dried root of Astragalus membranaceus or related species, a prominent herb in Traditional Chinese Medicine (TCM). It is traditionally valued for enhancing vitality and supporting immune function, particularly in conditions related to 'qi deficiency.' Its primary applications, supported by modern research, include immune modulation, kidney protection, anti-inflammatory effects, and as an adjunctive therapy in cancer treatment. The active constituents responsible for its therapeutic effects are primarily polysaccharides, saponins, and flavonoids. While research into Astragalus is ongoing with multiple clinical trials and meta-analyses, the overall evidence quality is moderate, often limited by methodological inconsistencies and heterogeneity across studies.
Benefits
Astragalus root extract offers several evidence-based benefits. It has shown promise in improving kidney function, with a retrospective study reporting statistically significant improvement in estimated glomerular filtration rate (eGFR) in patients with mild to moderate chronic kidney disease (CKD) after 3.4 months of use. As an immune modulator, meta-analyses suggest that astragalus-containing formulas can enhance both humoral and cellular immunity while reducing pro-inflammatory mediators. In cancer care, particularly for colorectal cancer, a meta-analysis indicated that astragalus combined with chemotherapy improved tumor response rates, quality of life, and reduced chemotherapy side effects; however, the methodological quality of included RCTs was generally low. Additionally, preclinical and animal studies suggest liver protective effects, including reduction of liver enzymes (AST, ALT) and protection against drug-induced liver injury through anti-inflammatory and antioxidant mechanisms. The clinical significance of these benefits varies, with clearer evidence in kidney function and as a cancer adjunct, though further high-quality research is needed.
How it works
Astragalus exerts its therapeutic effects primarily through its active compounds, including polysaccharides and saponins. These compounds modulate immune responses by enhancing both humoral and cellular immunity. Its anti-inflammatory properties are mediated by inhibiting MAPK signaling pathways and activating Nrf2 and autophagy pathways, which are crucial for cellular defense and detoxification. Astragalus also possesses antioxidant capabilities, reducing oxidative stress in vital organs like the liver and kidneys. At a molecular level, it interacts with inflammatory cytokines and pathways involved in cell survival and apoptosis, such as Bcl-2 and Bax. While polysaccharides are water-soluble and absorbed in the gut, detailed human pharmacokinetics are still limited, and bioavailability can depend on the extraction method.
Side effects
Astragalus root extract is generally considered safe with a low incidence of adverse effects in clinical studies. Specific common side effects (occurring in more than 5% of users) are not well-documented, but mild gastrointestinal symptoms may occasionally occur. There are no robustly reported significant drug interactions or contraindications; however, caution is advised when combining astragalus with immunosuppressants due to its immune-modulating effects, or with anticoagulants due to potential, though unconfirmed, effects on blood clotting. Sufficient safety data for special populations, such as pregnant or breastfeeding individuals, are lacking, and therefore its use in these groups is not recommended without medical supervision. Overall, serious adverse events are rare, but comprehensive long-term safety data are still limited.
Dosage
The optimal dosage of astragalus root extract can vary depending on the specific formulation and intended use. In a study on chronic kidney disease, a median daily dose of 3.0 grams of astragalus root was used for approximately 3.4 months. Traditional Chinese Medicine (TCM) practices typically recommend daily doses of 3-9 grams of the dried root. There is currently no established maximum safe dose, and clinical trials generally utilize moderate doses that fall within these traditional ranges. The timing of administration and the form of the supplement (e.g., standardized extract versus raw decoction) can influence absorption and efficacy, but standardized recommendations for these factors are not yet available. It is advisable to consult a healthcare professional for personalized dosage guidance.
FAQs
Is astragalus effective for kidney disease?
Evidence suggests astragalus may offer modest improvement in mild to moderate chronic kidney disease (CKD), particularly in eGFR. However, larger, high-quality randomized controlled trials are needed to confirm these findings.
Can astragalus be used with chemotherapy?
Some evidence indicates that astragalus, when combined with chemotherapy, may improve tumor response and quality of life while reducing side effects. However, the quality of these studies is generally low, warranting cautious interpretation.
Is astragalus safe for long-term use?
Astragalus is generally considered safe with a low incidence of side effects. However, comprehensive long-term safety data are limited, and continuous use should ideally be monitored by a healthcare professional.
When is the best time to take astragalus?
There is no scientific consensus on the optimal timing for taking astragalus. Traditionally, it is taken daily, often in divided doses, but specific recommendations depend on the product and individual needs.
Research Sources
- https://www.frontiersin.org/journals/pharmacology/articles/10.3389/fphar.2022.775798/full – This retrospective clinical study involving 37 patients with mild to moderate chronic kidney disease (CKD) found a statistically significant improvement in estimated glomerular filtration rate (eGFR) after a median of 3.4 months of astragalus-containing preparations. The study suggests a potential benefit of astragalus in CKD, though its retrospective nature and small sample size limit the generalizability of the findings.
- https://pmc.ncbi.nlm.nih.gov/articles/PMC6700271/ – This meta-analysis of randomized controlled trials (RCTs) investigated the use of astragalus as an adjunct to chemotherapy in 1,409 colorectal cancer patients. It concluded that astragalus improved tumor response rates, quality of life, and reduced chemotherapy-related side effects. However, the authors noted that the included RCTs generally suffered from low methodological quality, suggesting the need for more rigorous studies.
- https://www.dovepress.com/research-progress-on-the-treatment-of-related-diseases-with-astragalus-peer-reviewed-fulltext-article-DDDT – This narrative review synthesizes preclinical data and some clinical observations regarding astragalus's protective effects on the liver and lungs. It highlights astragalus's anti-inflammatory and antioxidant mechanisms, suggesting its potential to reduce liver enzyme levels (AST, ALT) and protect against drug-induced liver injury. The review emphasizes that most evidence is preclinical, with limited human clinical data.
- https://www.herbalgram.org/resources/herbclip/issues/2025/issue-762/astragalus-root-extract/ – This source summarizes meta-analyses on the immune-modulating effects of astragalus. It indicates that astragalus-containing formulas can improve both humoral and cellular immunity and reduce pro-inflammatory mediators. The summary notes that while promising, potential publication bias in the included studies should be considered.
