Supplement analysis backed by scientific evidence · PT

← All supplements
Limited evidenceImmunity

Astragalus

Almost the entire clinical literature on Astragalus comes from Chinese trials of injectable decoctions added to conventional drugs, not from the oral capsules sold in the West. Cochrane rated the kidney-disease evidence as too poor to draw conclusions, and there are essentially no good trials of oral astragalus for immunity in healthy people.

What the science says

  • Chronic kidney disease Limited evidence

    The 2014 Cochrane review of 22 studies (1,323 participants) found suggestions of reduced proteinuria and improved creatinine clearance, but every included study was at high or unclear risk of bias, follow-up was short, and no trial reported patient-important outcomes such as death or progression to dialysis. Cochrane's conclusion was that current evidence is insufficient to support its use.

  • Adjunct to platinum chemotherapy in lung cancer Limited evidence

    A 2019 meta-analysis of Astragalus injection combined with platinum chemotherapy in advanced non-small cell lung cancer reported improved response rates, performance status and reduced chemotherapy toxicity. These are unblinded trials of an intravenous preparation in Chinese hospitals, with well-documented publication bias in this literature — the findings do not transfer to oral supplements.

  • Immune support in healthy adults Limited evidence

    Claims about NK-cell activity and interferon production rest mainly on cell-culture and animal work plus small mechanistic studies. No adequately powered RCT shows that oral astragalus reduces the frequency or duration of infections in healthy people.

Dosage & safety

Studied doseTraditional decoction: 9-30 g/day of dried root. Commercial oral extracts are usually 500-1,500 mg/day of a 4:1 to 10:1 extract, sometimes standardized to astragalosides or polysaccharides — but these doses are conventional rather than evidence-derived. The trial literature is dominated by intravenous Astragalus injection at 20-60 mL/day, which is not a consumer product.
SafetyOral astragalus root appears well tolerated in short-term use, with occasional GI upset and rash. Injectable preparations have caused anaphylaxis and fever. Astragalus may lower blood glucose and blood pressure, so watch for additive effects with antidiabetic and antihypertensive drugs. Its immunostimulant reputation makes it a theoretical problem alongside ciclosporin, tacrolimus and other immunosuppressants, and caution is advised in autoimmune disease. Some Astragalus species (not A. membranaceus) accumulate selenium or contain swainsonine and are toxic — species identity on the label matters. Insufficient safety data in pregnancy and lactation.

Scientific references

Where to buy

Nutricost, Astragalus Root , 550 mg , 240 Capsules

View on iHerb

Referral link — this site may earn a commission on purchases.

Related in Immunity