Astragalus Side Effects & Precautions

Astragalus Side Effects & Precautions
Page content


Astragalus is native to China and has been used for hundreds of years in traditional Chinese medicine (TCM). About 2,000 species exist but not all are the same. The primary species used for medicinal purposes is Astragalus membranaceus.

Historically, astragalus has been used (normally with other herbs) to strengthen and support the immune system. Today, it is used in TCM to treat viral infections. Clinical studies have shown astragalus to be an effective remedy in the prevention of the common cold.

Astragalus Side Effects & Precautions

No serious side effects have been reported when used alone and taken at recommended doses. The most common side effect is mild stomach upset. Although it is generally considered as safe, there are precautions that should be taken.


As mentioned above, there are about 2,000 species of astragalus. Some of these species contain toxins that are known to cause poisoning in livestock. Animals that would eat it would drool, run in circles, or stagger (thus giving these plants the name locoweed - loco meaning crazy). Locoweed grows wild in the western part of the United States.


People who have allergies to plants belonging in the Leguminosae (pea) family may have an allergic reaction to astragalus.

Blood Sugar

Based on limited research, astragalus may decrease blood glucose (sugar) levels. People with hypoglycemia or diabetes should use caution when taking. Talk with your health care provider, especially if taking medications or insulin.

Blood Pressure

Astragalus has been noted to affect blood pressure. Doses above 30 grams have been known to increase it and doses below 15 grams have been known to decrease it. People with blood pressure problems or taking medications for blood pressure should use caution when taking and consult with their health care provider.


Astragalus may increase ones risk of bleeding. People with bleeding disorders or taking medications that increases ones risk of bleeding (such as aspirin and coumadin) should avoid taking unless approved by a health care provider.

Auto-Immune Diseases

People with auto-immune diseases (including rheumatoid arthritis, lupus, and multiple sclerosis) should avoid taking astragalus.


People taking medications that suppress the immune system should avoid use. This includes corticosteroids and certain medications taken by cancer patients and transplant recipients.

People taking diuretics should use caution when taking astragalus to prevent dehydration and electrolyte imbalance.


There is not enough data to recommend astragalus to children and women who are pregnant or breastfeeding.

Doses above 28 grams may make ones immune system less active. Astragalus side effects can be avoided by most if used as directed.

Sources Used

National Center for Complementary and Alternative Medicine: Astragalus -

University of Maryland Medical Center: Astragalus -

eNotAlone: Astragalus: Dosing and Safety -

Photo Credit

Image courtesy of CC-BY-SA-3.0 / Doronenko at Wikimedia.


Please read this disclaimer regarding the information contained within this article.