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Dosing

The below doses are based on scientific research, publications, traditional use, or expert opinion. Many herbs and supplements have not been thoroughly tested, and safety and effectiveness may not be proven. Brands may be made differently, with variable ingredients, even within the same brand. The below doses may not apply to all products. You should read product labels, and discuss doses with a qualified healthcare provider before starting therapy.

Standardization

Standardization involves measuring the amount of certain chemicals in products to try to make different preparations similar to each other. It is not always known if the chemicals being measured are the "active" ingredients. Anecdotal reports have recommended astragalus to be standardized to a minimum of 0.4% 4-hydroxy-3-methoxy-isoflavone-7-glycoside per dose. However, since astragalus is often added to herbal mixtures with unclear amounts used, standardization is not always possible.

Adults (18 years and older)

General use by mouth: In Chin

ese medicine, astragalus is used in soups, teas, extracts, and pill form. In practice and in most scientific studies, astragalus is one component of multi-herb mixtures. Therefore, precise dosing of astragalus alone is not clear. Safety and effectiveness are not clearly established for any particular dose. Various doses of astragalus have been used or studied, including 250 to 500 milligrams of extract taken 4 times daily; 1 to 30 grams of dried root taken daily (doses as high as 60 grams have been reported); or 500 to 1000 milligrams of root capsules taken 3 times daily. Dosing of tinctures or fluid extracts depends on strength of preparations.

Intravenous (IV): For non-small cell lung cancer, 60ml has been given intraveneously per day.

Note: In theory, consumption of the tragacanth (gummy sap derived from astragalus) may reduce absorption of drugs taken by mouth, and should be taken at separate times.

Children (younger than 18 years)

There is not enough scientific data to recommend astragalus for use in children.

Safety

The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.

Allergies

In theory, patients with allergies to members of the Leguminosae (pea) family may react to astragalus. Cross-reactivity with quillaja bark (soapbark) has been reported for astragalus gum tragacanth.

Side Effects and Warnings

Some species of astragalus have caused poisoning in livestock, although these types are usually not used in human preparations (which primarily include Astragalus membranaceus ). Livestock toxicity, referred to as "locoweed" poisoning, has occurred with species that contain swainsonine ( Astragalus lentiginosus, Astragalus mollissimus, Astragalus nothrosys, Astragalus pubentissimus, Astragalus thuseri, Astragalus wootoni ), or in species that accumulate selenium ( Astragalus bisulcatus, Astragalus flavus, Astragalus praelongus, Astragalus saurinus, Astragalus tenellus ).

Overall, it is difficult to determine the side effects or toxicity of astragalus, because it is most commonly used in combination with other herbs. There are numerous reports of side effects ranging from mild to deadly in the United States Food and Drug Administration computer database, although most of these are with multi-ingredient products, and cannot be attributed to astragalus specifically. Astragalus used alone and in recommended doses is traditionally considered to be safe, although safety is not well studied. The most common side effects appear to be mild stomach upset and allergic reactions. In the United States, tragacanth (astragalus gummy sap) has been classified as GRAS (generally recognized as safe) for food use, but astragalus does not have GRAS status.

Based on preliminary animal studies and limited human research, astragalus may decrease blood sugar levels. Caution is advised in patients with diabetes or hypoglycemia, and in those taking drugs, herbs, or supplements that affect blood sugar. Serum glucose levels may need to be monitored by a healthcare professional, and medication adjustments may be necessary.

Based on anecdotal reports and preliminary laboratory research, astragalus may increase the risk of bleeding. Caution is advised in patients with bleeding disorders or taking drugs that may increase the risk of bleeding. Dosing adjustments may be necessary.

Preliminary reports of human use in China have noted decreased blood pressure at doses below 15 grams and increased blood pressure at doses above 30 grams. Animal research suggests possible blood pressure lowering effects. Due to a lack of well-designed studies, no firm conclusions can be drawn. Nonetheless, people with abnormal blood pressure or taking blood pressure medications should use caution and be monitored by a qualified healthcare professional. Palpitations have been noted in human reports in China.

Based on animal study, astragalus may act as a diuretic and increase urination. In theory, this may lead to dehydration or metabolic abnormalities. There is one report of pneumonia in an infant after breathing in an herbal medicine powder including Astragalus sarcocolla .

Astragalus may increase growth hormone levels.

Pregnancy and Breastfeeding

There is not enough scientific evidence to recommend the safe use of Astragalus membranaceus during pregnancy or breastfeeding. Studies of toxic astragalus species, such as Astragalus lentiginosus or Astragalus mollissimus (locoweed) have reported harmful effects during animal pregnancies, leading to abortions or abnormal heart development.

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