Ginseng (American)

Common Names

  • Xi yang shen
  • Tienchi ginseng
  • western ginseng
  • five-fingers

For Patients & Caregivers

American ginseng has not been shown to treat or prevent cancer.

American ginseng has been shown to lower blood sugar levels in humans. Scientists think that the medicinal properties of this herb come from its components called ginsenosides. Most research has been done on another species, Panax ginseng. These studies indicate that ginsenosides both stimulate and inhibit the central nervous system in humans and stimulate the immune system in mice.
American ginseng was shown to reduce the number and severity of colds, and improve working memory in healthy adults. It also showed anticancer properties in lab studies, and may be useful in reducing cancer-related fatigue.

American ginseng decreases the anticoagulant effects of warfarin, a commonly used anticoagulant. Breast cancer patients should use this herb with caution because it can stimulate the growth of breast cancer cells.

  • To improve athletic performance
    No scientific evidence supports this use.
  • To prevent and treat cancer
    There are no data to back this claim. But American ginseng helps improve cance-related fatigue and improves quality of life.
  • To treat diabetes
    A few studies show a blood glucose-lowering effect of American ginseng.
  • To stimulate the immune system
    Some studies show an immunostimulant effect in animals. Human data are lacking.
  • For increased strength and stamina
    Although American ginseng is often promoted for this use, human data are lacking.
  • You are taking warfarin or other blood thinners (American ginseng may interfere with the action of the anticoagulant).
  • You are taking drugs that are substrates of cytochrome P450 (CYP) 3A4 (American ginseng may make the drugs less effective).
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For Healthcare Professionals

Panax quinquefolius

A popular herb often confused with Asian or Panax ginseng, American ginseng has unique medicinal properties. It is frequently used in Chinese medicine to nourish “Yin” (1). American ginseng is also used in supplemental form to improve athletic performance, strength and stamina, and to treat diabetes and cancer. The saponin glycosides, also known as ginsenosides or panaxosides, are thought responsible for the herb’s biological effects.
Ginsenosides have both stimulatory and inhibitory effects on the CNS (4), alter cardiovascular tone, enhance humoral and cellular-dependent immunity, and exert anticancer effects in vitro (3) (15) (16).

Current data suggest that American ginseng may improve glucose control in diabetics (2) (6), and that it is safe for long-term use (25). It also demonstrated a modest effect in reducing the number and severity of colds (12); enhanced working memory in young (21) and middle aged (27) healthy adults, as well as in patients with schizophrenia (24).

The anticancer activity of American ginseng was enhanced when combined with antioxidants (14). In other studies, the herb showed synergistic effects with 5-fluorouracil against colorectal cancer cells (17); and conferred protection against oxidative stress in irradiated human lymphocytes (18).
Data from an epidemiological study indicate that American ginseng improves survival and quality of life in breast cancer patients (13). Findings from a randomized controlled trial support its benefits in improving cancer-related fatigue (23).

  • Cancer prevention
  • Cancer treatment
  • Diabetes
  • Health maintenance
  • Immunostimulation
  • Strength and stamina

Ginsenosides are thought responsible for American ginseng’s activity, although the exact mechanism of action is unknown. Related species, such as Panax ginseng, have been the focus of most laboratory and clinical research. Experiments using extracts from these species indicate that ginsenosides stimulate and inhibit the CNS (4). The extracts also stimulate TNF alpha production by alveolar macrophages (10).

The Rg1 ginsenoside present in American ginseng is associated with improvements in humoral and cell-mediated immune response and increases in T helper cells, T lymphocytes, and NK cells in mice (5). American ginseng was also shown to lower serum glucose and may affect carbohydrate metabolism (2) (6).

Several ginsenosides demonstrated anticancer properties in vitro  (3). Current data suggest that the antiproliferative effects of American ginseng are due to compound K, a metabolite of the ginsenoside Rb1, but not Rb1 as previously thought (22). In another study, the herb was shown to significantly attenuate azoxymethane/dextran sodium sulfate (DSS)-induced colon carcinogenesis by reducing the colon tumor number and tumor load, associated with suppression of DSS-induced proinflammatory cytokine activation (26).

Breast cancer patients should use this product with caution as American ginseng may stimulate the growth of breast cancer cells (9).

Warfarin: American ginseng has been shown to antagonize warfarin’s effects (11).
Cytochrome P450 (CYP) 3A4 substrates: Certain ginsenosides can induce CYP3A4 and may affect the metabolism of some drugs that are substrates of this enzyme  (19) (20).

Reductions in PT, PTT, and INR and blood glucose may occur.
 (8) (11)

  1. Huang KC. The Pharmacology of Chinese Herbs, 2nd ed. New York: CRC Press; 1999.
  2. Vuksan V, et al. American ginseng (Panax quinquefolius L) reduces postprandial glycemia in nondiabetic subjects and subjects with type 2 diabetes mellitus. Arch Intern Med 2000;160:1009-13.
  3. Shin HR, et al. The cancer-preventive potential of Panax ginseng: a review of human and experimental evidence. Cancer Causes Control 2000;11:565-76.
  4. Attele AS, Wu JA, Yuan CS. Ginseng pharmacology: multiple constituents and multiple actions. Biochem Pharmacol 1999;58:1685-93.
  5. Chen SE. American ginseng. III. Pharmacokinetics of ginsenosides in the rabbit. Eur J Drug Metab Pharmacokinet 1980;5:161-8.
  6. Vuksan V, et al. American ginseng (Panax quinquefolius L.) attenuates postprandial glycemia in a time-dependent but not dose-dependent manner in healthy individuals. Am J Clin Nutr 2001;73:753-8.
  7. Brinker F. Herb Contraindications and Drug Interactions, 3rd ed. Sandy (OR): Eclectic Medical Publications; 2001.
  8. Vuksan V, et al. American ginseng improves glycemia in individuals with normal glucose tolerance: effect of dose and time escalation. J Am Coll Nutr 2000;6:738-44.
  9. Amato P, Christophe S, Mellon PL. Estrogenic activity of herbs commonly used as remedies for menopausal symptoms. Menopause 2002;9:145-50.
  10. Assinewe VA, et al. Extractable polysaccharides of Panax quinquefolius L. (North American ginseng) root stmulate TNFalpha production by alveolar macrophages. Phytomedicine 2002;9:398-404.
  11. Yuan CS, et al. Brief Communication: American Ginseng reduces Warfarin’s effect in healthy patients. Annals of Internal Medicine 2004;141:23-27.
  12. Predy GN, et al. Efficacy of an extract of North American ginseng containing poly-furanosyl-pyranosyl-saccharides for preventing upper respiratory tract infectons: a randomized controlled trial. CMAJ 2005;173(9):1043-8.
  13. Cui Yong, et al. Association of ginseng use with survival and quality of life among breast cancer patients. Am J Epidemiol 2006; 163(7):645-53.
  14. Li B, Wang CZ, He TC, et al. Antioxidants potentiate American ginseng-induced killing of colorectal cancer cells. Cancer Letters. 2010;289(1):62-70.
  15. Li B, Zhao J, Wang CZ, et al. Ginsenoside Rh2 induces apoptosis and paraptosis-like cell death in colorectal cancer cells through activation of p53. Cancer Lett. 2011 Feb 28;301(2):185-92.
  16. Xie JT, Du GJ, McEntee E, et al. Effects of Triterpenoid Glycosides from Fresh Ginseng Berry on SW480 Human Colorectal Cancer Cell Line. Cancer Res Treat. 2011 Mar;43(1):49-55.
  17. Li XL, Wang CZ, Sun S, et al. American ginseng berry enhances chemopreventive effect of 5-FU on human colorectal cancer cells. Oncol Rep. 2009 Oct;22(4):943-52.
  18. Lee TK, O’Brien KF, Wang W, et al. Radioprotective effect of American ginseng on human lymphocytes at 90 minutes postirradiation: a study of 40 cases. J Altern Complement Med. 2010 May;16(5):561-7.
  19. Hao M, Ba Q, Yin J, et al. Deglycosylated ginsenosides are more potent inducers of CYP1A1, CYP1A2 and CYP3A4 expression in HepG2 cells than glycosylated ginsenosides. Drug Metab Pharmacokinet. 2011;26(2):201-5.
  20. Hao M, Zhao Y, Chen P, et al. Structure-activity relationship and substrate-dependent phenomena in effects of ginsenosides on activities of drug-metabolizing P450 enzymes. PLoS One. 2008 Jul 16;3(7):e2697.
  21. Scholey A, Ossoukhova A, Owen L, et al. Effects of American ginseng (Panax quinquefolius) on neurocognitive function: an acute, randomised, double-blind, placebo-controlled, crossover study. Psychopharmacology (Berl). 2010 Oct;212(3):345-56.
  22. Wang CZ, Du GJ, Zhang Z, et al. Ginsenoside compound K, not Rb1, possesses potential chemopreventive activities in human colorectal cancer. Int J Oncol. 2012 Jun;40(6):1970-6.
  23. Barton DL, Liu H, Dakhil SR, et al. Wisconsin Ginseng (Panax quinquefolius) to improve cancer-related fatigue: a randomized, double-blind trial, N07C2. J Natl Cancer Inst. 2013 Aug 21;105(16):1230-8.
  24. Chen EY, Hui CL. HT1001, a proprietary North American ginseng extract, improves working memory in schizophrenia: a double-blind, placebo-controlled study. Phytother Res. 2012 Aug;26(8):1166-72.
  25. Mucalo I, Jovanovski E, Vuksan V, Božikov V, Romić Z, Rahelić D. American Ginseng Extract (Panax quinquefolius L.) Is Safe in Long-Term Use in Type 2 Diabetic Patients. Evid Based Complement Alternat Med. 2014;2014:969168.
  26. Yu C, Wen XD, Zhang Z, et al. American ginseng attenuates azoxymethane/dextran sodium sulfate-induced colon carcinogenesis in mice. J Ginseng Res. 2015 Jan;39(1):14-21.
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