Panax ginseng is one of the most commonly used and highly researched species of ginseng. This species, which is native to China, Korea, and Russia, has been an important herbal remedy in traditional Chinese medicine for thousands of years, where it has been used primarily as a treatment for weakness and fatigue (1)
The main active agents in Panax ginseng are ginsenosides, which are triterpene saponins. The majority of published research on the medicinal activity of Panax ginseng has focused on ginsenosides (2). These are the compounds to which some ginseng products are now standardized.
Ginseng products are popularly referred to as “tonics,”a term that has been replaced by “adaptogens”in much of the alternative medicine literature. The term “adaptogen” denotes an agent that purportedly “increases resistance to physical, chemical, and biological stress and builds up general vitality, including the physical and mental capacity for work.” (3)
Research reviews suggest that extracts of Panax ginseng affect the hypothalamus-pituitary-adrenal axis and the immune system, which could account for many of the documented effects (1,4). Animal models and in vitro studies mentioned in these reviews, indicate that Panax ginseng enhances phagocytosis, natural killer cell activity, and the production of interferon; improves physical and mental performance in mice and rats; causes vasodilation; increases resistance to exogenous stress factors; and affects hypoglycaemic activity.
Panax ginseng is used primarily to improve psychological function, exercise performance, immune function, and conditions associated with diabetes. Traditional Chinese medicine and many current research studies often use products that combine ginseng with other herbal medicines or vitamins (5-8). Because of the use of combination products and the limitations of some studies on ginseng (e.g., poor methodological quality, research focusing on healthy volunteers, small sample size, unstandardized ginseng preparations, varying doses),it is difficult to draw conclusions about some of the clinical effects of ginseng.
Psychological Function
Trials investigating the effects of Panax ginseng on various psychological parameters have shown positive effects, no effects, or both. In one study of 112 healthy volunteers older than 40 years, the administration of 400 mg per day of a standardized ginseng for eight weeks resulted in better and faster simple reactions and abstract thinking, but no change in concentration, memory, or subjective experience (9). The results of two small studies, each including about 30 young, healthy volunteers who received 200 mg of Panax ginseng extract daily for eight weeks, showed improvement in certain psychomotor functions (i.e., better attention, processing ,and auditory reaction time),social functioning, and mental health (10,11).
A study of 384 postmenopausal women who were randomized to receive placebo or ginseng for 16 weeks showed improvements in three subsets of a Psychological General Well-Being index (12).
In addition, a small study of 20 healthy young volunteers who received a single 400-mg dose of ginseng found improvement in cognitive performance, secondary memory performance, speed of performing memory tasks, and accuracy of attentional tasks .However, another study showed no effect on positive affect, negative affect, or total mood disturbance in 83 young healthy volunteers who took 200 to 400 mg per day of standardised extract for eight weeks (13).
Fatigue Reduction and Physical Performance
The European Medicines Agency has deemed panax finseng to be a traditional herbal medicinal product for symptoms of asthenia such as fatigue and weakness (14-16).
A recent meta-analysis of the efficacy of ginseng supplements on fatigue and physical performance reviewed data from 155 randomised controlled trials (17). It found a statistically significant efficacy of ginseng supplements in the reduction of fatigue. The effectiveness of ginseng in the treatment of fatigue has also been recently confirmed in a randomised, placebo controlled, double-blind pilot study in patients suffering from multiple sclerosis (18). Immune System A study of 227 healthy volunteers demonstrated that daily administration of 100 mg of standardised extract for 12 weeks enhanced the efficacy of polyvalent influenza vaccine (19). The patients who received ginseng had a lower incidence of influenza and colds, higher antibody titres, and higher natural killer cell activity levels. Another study in 60 healthy volunteers showed enhanced chemotaxis, phagocytosis, increased total lymphocyte count, and increased numbers of T helper cells in those who received a dosage of 100 mg twice daily for eight weeks (20). In a study of 75 patients with acute exacerbation of chronic bronchitis who were treated with antibiotics or antibiotics plus ginseng, those in the ginseng group showed faster bacterial clearance (21).
References
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2. World Health Organization. WHO monographs on selected medicinal plants. Geneva: World Health Organization, 1999.
3. Robbers JE, Tyler VE. Tyler’s Herbs of choice: the therapeutic use of phytomedicinals. New York, N.Y.: Haworth Herbal Press, 1999
4. Vogler BK, Pittler MH, Ernst E. The efficacy of ginseng. A systematic review of randomised clinical trials. Eur J Clin Pharmacol 1999;55:567-75.
5. Caso MA, Vargas RR, Salas VA, Begoña IC. Double-blind study of a multivitamin complex supplemented with ginseng extract. Drugs under experimental and clinical research. 1996;22(6):323-9.
6. Pieralisi G, Ripari P, Vecchiet L. Effects of a standardized ginseng extract combined with dimethylaminoethanol bitartrate, vitamins, minerals, and trace elements on physical performance during exercise. Clinical therapeutics. 1991;13(3):373-82.
7. Kennedy DO, Scholey AB, Wesnes KA. Modulation of cognition and mood following administration of single doses of Ginkgo biloba, ginseng, and a ginkgo/ginseng combination to healthy young adults. Physiology & behavior. 2002 Apr 15;75(5):739-51.
8. Wesnes KA, Ward T, McGinty A, Petrini O. Without Title. Psychopharmacology. 2000 Nov 18;152(4):353-61.
9. Sørensen H, Sonne J. A double-masked study of the effects of ginseng on cognitive functions. Current Therapeutic Research. 1996 Dec 1;57(12):959-68.
10. D'angelo L, Grimaldi R, Caravaggi M, Marcoli M, Perucca E, Lecchini S, Frigo GM, Crema A. A double-blind, placebo-controlled clinical study on the effect of a standardized ginseng extract on psychomotor performance in healthy volunteers. Journal of ethnopharmacology. 1986 Apr 1;16(1):15-22.
11. Ellis JM, Reddy P. Effects of Panax ginseng on quality of life. Annals of Pharmacotherapy. 2002 Mar;36(3):375-9.
12. Wiklund IK, Mattsson LA, Lindgren R, Limoni C. Effects of a standardized ginseng extract on quality of life and physiological parameters in symptomatic postmenopausal women: a double-blind, placebo-controlled trial. Swedish Alternative Medicine Group. International journal of clinical pharmacology research. 1999;19(3):89-99.
13. Cardinal BJ, Engels HJ. Ginseng does not enhance psychological well-being in healthy, young adults: results of a double-blind, placebo-controlled, randomized clinical trial. Journal of the American Dietetic Association. 2001 Jun 30;101(6):655-60.
14. http://www.ema.europa.eu/docs/en_GB/document_library/Herbal_-_Community_herbal_monograph/2014/05/WC500167387.pdf
15. http://www.ema.europa.eu/docs/en_GB/document_library/Herbal_-_Community_herbal_monograph/2014/05/WC500167387.pdf
16. http://www.ema.europa.eu/docs/en_GB/document_library/Herbal_-_List_of_references_supporting_the_assessment_report/2014/05/WC500167386.pdf
17. Bach HV, Kim J, Myung SK, Cho Y. Efficacy of Ginseng Supplements on Fatigue and Physical Performance: a Meta-analysis. Journal of Korean medical science. 2016 Dec 1;31(12):1879-86.
18. Etemadifar M, Sayahi F, Abtahi SH, Shemshaki H, Dorooshi GA, Goodarzi M, Akbari M, Fereidan-Esfahani M. Ginseng in the treatment of fatigue in multiple sclerosis: a randomized, placebo-controlled, double-blind pilot study. International Journal of Neuroscience. 2013 Jul 1;123(7):480-6.
19. Scaglione F, Cattaneo G, Alessandria M, Cogo R. Efficacy and safety of the standardised Ginseng extract G115 for potentiating vaccination against the influenza syndrome and protection against the common cold [corrected]. Drugs under experimental and clinical research. 1996;22(2):65-72.
20. Scaglione F, Ferrara F, Dugnani S, Falchi M, Santoro G, Fraschini F. Immunomodulatory effects of two extracts of Panax ginseng CA Meyer. Drugs under experimental and clinical research. 1990;16(10):537-42.
21. Scaglione F, Weiser K, Alessandria M. Effects of the standardized ginseng extract G115[R] in patients with chronic bronchitis: a nonblinded, randomised, comparative pilot study. Clin Drug Invest [New Zealand] 2001;21:41-5.
