Herbs & Supplements

Should I take it?

As its name indicates, American ginseng is native to North America--originally found in the central woodlands of the northern United States and southern Canada. Although it was used by Native Americans to treat several conditions, the North American medical community did not adopt its use as a medicinal plant until well after 1900. After being introduced to China in the 18th century, however, American ginseng was quickly adopted by practitioners of traditional Chinese medicine. Now, it is grown commercially in China and sometimes distributed back to North America. Because American ginseng is an international endangered species, its collection from wild sources has been strictly regulated for nearly 20 years. Wild American ginseng root is preferred to cultivated root; however, so it usually sells for a higher price. Therefore, the control of illegal harvesting of wild American ginseng from public land is a major problem for the U.S. National Park Service.

American ginseng plants are small--only about a foot tall. When mature, they have three or four leaf groups each containing five dark green leaves arranged in rough circles around short stems. The species name, quinquefolius, means "five-leaves". On a larger central stem at the center of each plant, a group of small red berries forms after little yellow flowers bloom in summer. In the wild, American ginseng grows in cool, dark, damp areas under the cover of trees. When it is grown as a crop, American ginseng must be shaded by awnings or trellises. Commercial cultivation is difficult and crops mature slowly.

Occasionally, the flower buds or young leaves of American ginseng have been made into tea. In fact, very early results from chemical analyses have found some medically active ingredients in American ginseng leaves and berries. The part of American ginseng currently used for medicine is the root. Harvested in the autumn from plants that are at least 4 years old, American ginseng roots are usually thick at the top and branch into two or sometimes three smaller sections toward the end. Smooth-skinned, the roots have a firm texture similar to carrots. They do not have a sweet smell like Panax ginseng roots, but they have a characteristic sweet/spicy taste that reminds some individuals of licorice. The roots typically are dried for use in medicine. American ginseng is also used in cosmetics, perfumes, soap, and soft drinks.

While it is related to Panax ginseng, which originated in Asia, American ginseng is a distinct species with a different chemical makeup than Panax ginseng. Most notably, American ginseng typically has higher levels of a chemical known as ginsenoside Rb1 than Panax ginseng and it has no ginsenoside Rf. Ginsenoside Rb1 is believed to limit or prevent the growth of new blood vessels. Ginsenoside Rf may be responsible for the pain-relieving effect associated with Panax ginseng.

Dosage and Administration

American ginseng has many oral dosage forms--most commonly fresh or dried root, capsules containing powdered root, or liquid tincture. Although dosing recommendations for American ginseng are not consistent, typical recommendations for most individuals are 200 mg to 500 mg twice a day. In one study, doses for children with ADHD were 200 mg of American ginseng with 50 mg of ginkgo biloba extract taken twice a day for 4 weeks. A study of American ginseng's ability to reduce blood sugar levels after meals for individuals with type 2 diabetes used doses 2 hours before meals. Participants in the study took up to 9,000 mg (9 grams) per day with no apparent increase in side effects. However, no additional reduction of blood sugar was seen from doses higher than 3,000 mg (3 grams) per day.

Summary

Classed as an adaptogen, American ginseng may be taken to increase the body's general resistance to stress and reduce some cold and flu symptoms. It has been shown in clinical studies to lower blood sugar levels, and it may also be useful in preventing damage from strokes and in relieving symptoms of ADHD. Its hormone-like effects are being studied for possible relief of menopausal symptoms.

Risks

Individuals who have heart conditions, endometriosis, schizophrenia, or hormone-dependent cancers should not take American ginseng. It should also be avoided by young children, individuals with insomnia, and pregnant or breast-feeding women. If individuals with diabetes take American ginseng, they should take no more than recommended doses and also check their blood sugar levels carefully to make sure they do not develop hypoglycemia.

Side Effects

Side effects attributed to American ginseng generally involve excitement of the central nervous system, including insomnia and restlessness.

Interactions

American ginseng may interfere with many prescription drugs, non-prescription products, and herbals, including:

• caffeine
• Central nervous system stimulants
• Drugs and herbals used for the treatment of diabetes
• Drugs used to treat schizophrenia
• MAO inhibitors
• warfarin

Last Revised October 17, 2007