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American Ginseng

American Ginseng Introduction

American ginseng, panax quinquefolius, is one of six ginseng species found worldwide. It is found primarily in eastern North America (Canada and US). American ginseng grows within forested and rocky slopes of mountainous areas with a temperate climate. Well-drained fertile soil is a necessity, along with being approximately 80% shaded. The plants themselves reach a height of 2 - 3 feet. They have broad dark green leaves with small pale flowers.

American ginseng has been harvested in the US for over 275 years. The Ginseng species of plants have been used in Asia for more than 2.000 years. 80-90% of the wild harvested American ginseng is exported to Hong Kong. It is the second largest exported herb next to garlic. The collection and sales of American ginseng is a big money maker. Because of this, there are many problems with illegal harvesting of wild ginseng.

Cultivated ginseng is believed to have less medicinal use than wild ginseng. American ginseng, as well as the other species of ginseng, has several active constituents. The main medicinal constituents are the ginsenosides. There are some 30 different ginsenosides present. Amounts vary, but are typically 2 - 3% in fresh root, and 5-17% in extracts. These approximated amounts are dependant upon the method of extraction and processing used. These ginsenosides can be divided into two classes; the protopanaxatriols and the protopanaxadiols. Protopanaxatriols are considered to be more stimulating, and the protopanaxadiols, more sedating. American ginseng also contains polysaccharides, lipids, sterols, and alcohols. [1]

The medicinal activity of American ginseng is believed to be greatest when the ratio between the Rg1 protopanaxatriol and the Rb1 protopanaxadiol is greater than 0.5. This is the excepted marker of high quality ginseng. [2] American ginseng tends to be less stimulating than the other ginseng species, namely Panax ginseng (Chinese or Korean) and Eleuthrococcus senticosus (Siberian ginseng). This is believed to be due to the larger amount of protopanaxadiols and the lesser amount of protopanaxatriols.

Traditionally ginseng has been used for immune enhancement, as a tonic, stimulant, and as an adaptogen herb.

American Ginseng Uses

Part Used

The root of American ginseng is used for medicinal, and associated therapeutic, benefit. The main and lateral roots have more active ingredients than the root hairs. The root must be harvested after 6 years of growth. Once harvested it is either categorized as either white or red ginseng. White ginseng is immediately sun-dried post harvest. Red ginseng is steamed, artificially dried, then sun-dried to yield its red color.

American Ginseng Uses:

American ginseng has been proven to be effective for a wide range of conditions. It is used for glycemic control, ADHD, cancer prevention, immune system enhancement, cardiovascular disease, and as a potential neuroprotective agent.

American ginseng may be an effective treatment for type II diabetes mellitus. It is capable of lowering the blood sugar after ingestion of carbohydrate-rich foods. American ginseng has been equally promising in studies at effectively lowering the postprandial glycemic values of both diabetic and non-diabetic individuals. [3] Ginseng is considered most effective when taken 40 minutes before eating food. [4] The activity of American ginseng in type II diabetes is believed to be due to a mechanism similar to that of sulfonylurea medications. [5] American ginseng is a known immune-stimulating. It has traditionally been used to increase immunological defense against disease and infection. Ingestion of American ginseng has been shown to stimulate the immune system via the molecule TNF-alpha. [6] This molecule is responsible for signaling white blood cells to migrate to areas of infection and inflammation. In addition, American ginseng exhibited certain immune enhancing properties in a study concerning the prevention of acute respiratory illness. American ginseng was shown to prevent acute respiratory illness (ARI) caused by nfluenza or RSV viruses. [7]

American ginseng may also yield certain anti-cancer properties. In study, it has been shown to inhibit breast cancer cell growth in vitro via the signaling molecule p21. [8] p21 is responsible for terminating cell cycles, and is often inactivated or mutated in cancer cells. American ginseng was also shown to act synergistically with conventional medications used to treat breast cancer. [9] American ginseng also has shown antioxidant activity. It is effective at decreasing the oxidation of LDL cholesterols. [10] Oxidized LDL is pathological for the development of atherosclerosis. Atherosclerosis can contribute to any cardiovascular disease, therefore supplementing with American ginseng may provide a protective means against the development of such chronic diseases of the heart.

Individuals with Attention deficit hyperactivity disorder (ADHD) may benefit from American ginseng as well. [11] It has been shown to improve symptoms in over 50% of participants in study, in as little as 2 weeks. Improvements also continued over the next 2 weeks, or until the completions of the study. However, it is important to note that the results of this study were obtained by using a synergistic combination of ginseng with ginkgo biloba, another popular herb.

American Ginseng Contraindications & Interactions

Ginseng Contraindications:

Ginseng is contraindicated in several conditions: asthma, acute infection, high blood pressure, and hemorrhage. [12]

Ginseng Interactions:

Ginseng can interact with several different medications. It is important to inform your physician of any medications, supplements, or botanicals that you are taking to avoid drug-herb interactions. One should always consult a physician before beginning any new treatment.

Individuals who are taking an MAOI (Monoamine oxidase inhibitor) should avoid using ginseng. Several case reports of increased mania symptoms from the drug-herb combination were reported. [13]

Individuals who are taking diuretics for high blood pressure or congestive heart failure should use caution when taking ginseng. There is a published case report of ginseng inducing resistance to diuretics. [14]

Individuals who are taking estrogens or corticosteroids should use caution when taking ginseng because there is the potential for additive effects due to the mechanism of action of ginseng. [15]

Individuals who are taking insulin for type I diabetes mellitus should have there blood sugar checked regularly when taking ginseng because of the possibility of certain synergistic effects. Ginseng has been shown to lower blood sugar. Individuals on insulin therapy may need to adjust their dose if taking ginseng. [16]

Ginseng may have some effect on the pharmacology of digoxin or its metabolism in the body. Those taking digoxin should not take ginseng concurrently. [17]

Ginseng has also been shown in study to reduce the effect of Warfarin. Warfarin is an anti-coagulant. Ginseng decreases the anti-coagulant effect of Warfarin, making the blood more likely to clot. This is extremely important for individuals with thrombosis or pulmonary embolism. [18]

American Ginseng Dosages

Ginseng can be taken in a variety of forms, including; dried root, tincture, tea, or standardized extract. The following dosages are for acute use, which should be limited to 1-2 weeks. These dosages can be reduced for long-term use or maintenance use.

When taking any form of ginseng it is advised to stop supplementation for one week, after 3 weeks of continually use, to avoid the possibility of developing ginseng abuse syndrome.

Form: Dosage:
Dried Root 0.5 - 3.0 grams per day
Standardized Extract 100 - 200 milligrams per day (4 - 7% ginsenosides)
1:5 Tincture 2 - 10 milliliters (ml) per day

American Ginseng Toxicities

Excessive use, overdose, or long-term usage can cause ginseng abuse syndrome. This is characterized by heart symptoms (palpitations, increased heart rate), nosebleeds, tremors, high blood pressure, insomnia, impaired sexual function, breast pain, and increased vaginal bleeding.


[1] Mills S, Bone K. Principles and Practice of Phytotherapy. Churchill Livingstone, London. 2000. p. 418-431.

[2] Mills S, Bone K. Principles and Practice of Phytotherapy. Churchill Livingstone, London. 2000. p. 418-431.

[3] Vuksan V et al. American ginseng (panax quinquefolius) reduces postprandial glcyemia in non-diabetic subjects and subjects with type II diabetes. Arch Intern Med. 2000 Apr 10; 160(7): 1009-1013.

[4] Vuksan V et al. American ginseng (panax quinquefolius) attenuates postprandial glycemia in a time dependant but not dose dependant manner in healthy individuals. Am J Clin Nutr. 2001 Apr; 73(4): 753-758.

[5] Rotshteyn Y, Zito SW. Application of modified in vitro screening procedure for identifying herbals possessing sulfonylurea like activity. J Ethnopharmacol. 2004 Aug; 93(2-3): 337-344.

[6] Zhou DL, Kitts DD. Peripheral blood mononuclear cell production on tumor necrosis factor alpha in response to North American ginseng stimulation. Can J Physiol Pharmacol. 2002 Oct; 80(10): 1030-1033.

[7] McElhaney JE et al. A placebo controlled trial of a proprietary extract of North American ginseng (CVT-E002) to prevent acute respiratory illness in institutionalized older adults. J Am Geratr Soc. 2004 Jan; 52(1): 13-19.

[8] Duda RB, Kang SS, Archer SY, Meng S, Hodin RA. American ginseng transcriptionally activates p21 mRNA in breast cancer cell lines. J Korean Med Sci. 2001 Dec 16; Suppl: S54-60.

[9] Duda RB, et al. American ginseng and breast cancer therapeutic agents synergistically inhibit MCF-7 breast cancer cell growth. J Surg Oncol. 1999 Dec; 72(4): 230-239.

[10] Li J, Huang M, Teoh H, Man RY. Panax quinquefolius saponins protect low-density lipoproteins from oxidation. Life Sci. 1999; 64(1): 53-62.

[11] Lyon MR, Cline JC, Totosy de Zepetnek J, Shan JJ, Pang P, Benishin C. Effect of herbal extract combination of panax quinquefolius and ginkgo biloba on attention deficit hyperactivity disorder: a pilot study. J Psychiatry Neruosci. 2001 May; 26(3): 221-228.

[12] Brinker F. Herb Contraindications and Drug Interactions, 3rd Ed. Eclectic Medical Publishing, Sandy, OR 2001. p.107-109.

[13] Brinker F. Herb Contraindications and Drug Interactions, 3rd Ed. Eclectic Medical Publishing, Sandy, OR 2001. p.107-109.

[14] Becker BN et al. Ginseng-induced diuretic resistance. JAMA. 1996 Aug 28; 276(8): 606-607.

[15] Miller LG. Herbal medicinals: selected clinical considerations focusing on known or potential drug-herb interactions. Arch Intern Med. 1998 Nov 9; 158(20): 2200-2211.

[16] Brinker F. Herb Contraindications and Drug Interactions, 3rd Ed. Eclectic Medical Publishing, Sandy, OR 2001. p.107-109.

[17] Miller LG. Herbal medicinals: selected clinical considerations focusing on known or potential drug-herb interactions. Arch Intern Med. 1998 Nov 9; 158(20): 2200-2211.

[18] Yuan CS et al. Brief communication: American ginseng reduces warfarin’s effect in healthy patients: a randomized controlled trial. Ann Intern Med. 2004 Jul 6; 141(1): 23-27.