Ginseng (Panax spp.): A Comprehensive Reference
1. Identity, Botanical Classification, and Natural Sources
Ginseng is the root of plants in the genus Panax, such as South China ginseng (P. notoginseng), Korean ginseng (P. ginseng), and American ginseng (P. quinquefolius), characterized by the presence of ginsenosides and gintonin. Ginseng is a plant in the family Araliaceae and the genus Panax, with the scientific name of Panax ginseng Meyer. The major commercial ginsengs are Panax ginseng Meyer (Korean ginseng), P. quinquefolius L. (American ginseng), and P. notoginseng (Burk.) FH Chen (Notoginseng).
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. American ginseng (Panax quinquefolius L.), also known as Xi Yang Shen (西洋参 Radix Panacis Quinquefolii), is indigenous to the United States and Canada.
The name Panax itself comes from the Greek panacea, meaning "cure-all." Most contend that the ren (人) portion of the name of ginseng root was based on the fact that many of the roots appear in the form of a human being with two legs (branching primary roots), a trunk, sometimes arms (lateral roots), and a head (stem scars).
1.1 Common Forms and Preparations
Panax ginseng often comes in either white or red ginseng forms. White ginseng is fresh ginseng that has been air-dried without being heated and is often used for long periods. Red ginseng is first steamed, then dried, and has a reddish color; due to its stimulating effects, it is typically used short-term.
Dammarane ginsenosides are transformed into compounds such as the ginsenosides Rg3, Rg5, and Rk1 by steaming and heating and are metabolized into metabolites such as compound K, ginsenoside Rh1, and protopanaxatriol by intestinal microflora. These metabolites are nonpolar, pharmacologically active and easily absorbed from the gastrointestinal tract.
Panax ginseng is available over the counter as whole root, liquid extract, capsule, and powder forms. Ginseng is often taken in doses of 200–400 mg/day, though doses vary based on the preparation. Ginseng can also be consumed as soup (e.g., Samgye-tang, which is ginseng chicken soup), tea (Insam-cha, or ginseng tea), liquor (Insam-ju, or ginseng liquor), or in energy drinks.
Ginseng products on the market show high variability in their composition and overall quality. This becomes a challenge for both consumers and health-care professionals who are in search of high-quality, reliable ginseng products with a proven safety and efficacy profile. Botanical extract standardization is of crucial importance in this context as it determines the reproducibility of the quality of the product. One well-characterized standardized extract is G115, which represents an example of an herbal drug preparation with constant safety and efficacy. Over many decades, extensive preclinical and clinical research has been conducted to evaluate the efficacy and safety of G115.
2. Traditional and Historical Use
2.1 Traditional Chinese Medicine (TCM)
Ginseng is a medicinal plant that has been used in medical practices for more than 2,000 years. The Shennong Bencao Jing (Shennong's Herbal Classic, 神農本草經), one of the first books specializing in herbal medicine, was edited in the 1st century AD. In this text, ginseng was first recognized as a medicinal herb by medical practitioners.
The foremost Chinese pharmacological text, Shennong's Classic of Herbal Medicine (Shennong Bencaojing; ca. 100 BC) describes the pharmacological use of ginseng for the first time. It is recorded that ginseng is a life-preserving drug and therefore leads to no harm even when it is consumed in large quantities and over long periods.
With its outstanding effects of nourishing, tranquilizing, and benefiting the mind, ginseng has been traditionally used as an herbal remedy for a variety of ailments, such as physical weakness, thirst, or insomnia with palpitations. At the same time, it has also been used as a tonic ingredient in the daily diet of the Chinese, and various kinds of supplements made from it have been used to prolong longevity.
In traditional Korean medicine, ginseng, possessing both sweet and slightly bitter flavor and warm qi (vital force or vital energy), enters the acupuncture meridians of the spleen, lungs, and heart. It is used to arouse energy, to fortify qi in the spleen and the lungs, to produce bodily fluids, to quench thirst, to stabilize the mind, and to increase wisdom.
2.2 Key Historical Texts
The characteristics of ginseng were described in historical documents such as the Shennong Bencao Jing, the Bencao Gangmu (本草綱目, written by Shizhen Li [李時珍] during the Ming Dynasty), and the Hyangyak-jibseongbang (鄕藥集成方) or the Donguibogam (東醫寶鑑, published during the Chosun Dynasty). The Shennong Bencao Jing (Divine Farmer's Classic of Materia Medica), the foundational herbal text from the Han Dynasty, lists Ren Shen as a "superior herb" — those that "prolong life, prevent aging, and support the spirit."
By the Tang Dynasty (618–907 AD), Korea became a major hub for ginseng cultivation, and the herb's fame spread across Asia and eventually to Europe by the 17th century. Because ginseng has been cultivated since the 15th century, the type of ginseng that appeared in the Shennong Bencao Jing may have been different from that which is currently in use.
2.3 Korean Traditional Use
Panax ginseng Meyer has been widely used as a tonic in traditional Korean, Chinese, and Japanese herbal medicines and in Western herbal preparations for thousands of years. In Korean traditional medicine, though herbal decoction, acupuncture, and moxibustion are all used to treat diseases, restorative medicines are the most widely preferred treatment method. As ginseng cultivation was realized, its use expanded even further in a wave of commercialization.
2.4 Native American Use of American Ginseng
In Native American traditions, American ginseng was used to treat headaches, fever, indigestion, and infertility. The plant's roots were often chewed directly or brewed into tea for medicinal purposes. American ginseng was later added to traditional Chinese medicine (TCM) Materia Medica books, where it was named Xi Yang Shen (西洋参 Radix Panacis Quinquefolii).
2.5 Adaptogen Concept
The efficacy of ginseng has been described as adaptogen activity — that is, substances that enhance the "state of nonspecific resistance" in stress — an activity that maintains homeostasis by normalizing the overall function of the body by nonspecifically increasing the body's resistance to external stress. The term "adaptogen" connotes 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. Key Constituents and Active Compounds
3.1 Ginsenosides (Saponins)
Among the diverse constituents of ginseng, its pharmacological activities can be attributed primarily to the triterpene saponins, generally known as ginsenosides. Up to now, over 100 ginseng saponins have been identified from the 11 different Panax species since their first description. A 2020 review updates the ginsenoside list from P. ginseng to 170 by the end of 2019.
Ginsenosides, also called ginseng saponins, are the major pharmacologically active ingredients of ginseng. The ginseng root contains 2–3% ginsenosides, of which Rg1, Rc, Rd, Re, Rb1, Rb2, and Rb0 are quantitatively the most important. American ginseng has a higher content of ginsenosides than other ginseng species such as Asian ginseng (Panax ginseng).
Ginsenosides have a 4-ring, steroid-like structure with sugar moieties attached, and more than 40 different ginsenosides have been identified and isolated from the root of P. ginseng. Saponins include four-ring triterpene saponins (protopanaxadiol-type saponin [PDS] and protopanaxatriol-type saponin [PTS]) and five-ring triterpene saponins (oleanane-type saponin). PDS and PTS are major effective components of ginseng.
Each ginsenoside may have different effects in pharmacology and mechanisms due to their different chemical structures. Among them the most commonly studied ginsenosides are Rb1, Rg1, Rg3, Re, Rd and Rh1.
3.2 Non-Saponin Constituents
Several classes of compounds have been isolated from ginseng root. These include triterpene saponins, essential oil-containing polyacetylenes and sesquiterpenes, polysaccharides, peptidoglycans, nitrogen-containing compounds, and various ubiquitous compounds such as fatty acids, carbohydrates, and phenolic compounds.
The active constituents of ginseng include ginsenosides, polysaccharides, and polyacetylenic alcohols. Several reports showed that the contents of total saponins in ginseng root were ranked as follows: rhizome > branch root > main root.
3.3 Mechanisms of Action
Although ginseng has been widely used for thousands of years, demonstrating various health benefits for a wide range of physiological ailments, there is surprisingly little scholarly knowledge of the molecular mechanisms of action for its bioactive ingredients. There is increasing evidence to suggest that ginseng saponins are involved in the regulation of hormone receptors, which are linked to a diverse array of signaling pathways.
Ginsenosides, the major pharmacologically active ingredients of ginseng, appear to be responsible for most of the activities of ginseng including vasorelaxation, antioxidation, anti-inflammation and anti-cancer.
Modern pharmacological studies have shown that PDS and PTS have various effects such as anti-fatigue, anti-shock, anti-tumor, blood sugar regulation, immunoregulation, and the protection of liver, kidney, heart, spleen, thymus, and so on.
Ginsenosides and other active ingredients may improve the state of chronic inflammation of the body by inhibiting the activation of the TLR signaling pathway and the release of inflammatory factors.
4. Scientific Evidence by Area of Use
4.1 Fatigue (General and Disease-Related)
A meta-analysis assessed the efficacy and safety of ginseng and ginseng herbal formulas for fatigue in randomized clinical trials (RCTs), searching PubMed, Embase, Cochrane, Web of Science, and AMED databases from inception to July 6, 2022. Outcomes included fatigue severity, quality of life, and adverse events. Quality of evidence was assessed using the Cochrane Risk of Bias Tool, and 19 RCTs were included. The authors found that ginseng was associated with reduction in fatigue, especially when using a ginseng formula and among patients with chronic fatigue, compared to placebo/waiting list, without increasing adverse events. They also found a trend toward improvement in quality of life with ginseng compared to controls.
A 2023 review of 19 studies (2,413 participants) suggested two notable results: Asian ginseng alone may have a small beneficial effect on general fatigue (not related to specific diseases); and certain ginseng herbal formulas containing other ingredients may be beneficial for patients with chronic fatigue, but not ginseng alone, and the effect size is small.
A meta-analysis included 12 randomized controlled trials containing 1,298 patients. In the fixed-effect meta-analysis, ginseng supplements had a statistically significant efficacy on disease-related fatigue reduction (standardized mean difference = 0.33, 95% confidence interval = 0.44–0.22).
For chronic fatigue syndrome (CFS) specifically, a systematic review found only 2 studies enrolling 68 patients were eligible, including one randomized clinical trial and one prospective observational study. The certainty of evidence in the effectiveness outcome was low and moderate from both studies, while the safety evidence was very low. The paucity of data warrants limited confidence.
4.2 Cancer-Related Fatigue
A systematic review identified a total of two clinical trials and one retrospective review examining the impact of American ginseng on cancer-related fatigue (CRF) symptoms, three studies testing Asian ginseng, and two trials conducted using Korean ginseng. The quality of the selected studies varied greatly. All three types of ginseng were tolerated well with few low-grade adverse events.
American ginseng, containing more than 5% ginsenosides, consumed at the dosage of 2,000 mg/day for up to eight weeks, significantly reduced fatigue. Asian ginseng, containing ≥ 7% ginsenosides, relieved symptoms of fatigue at the dosage of 400 mg/day in the majority of patients with CRF. Korean ginseng, consumed at the dosage of 3,000 mg/day for 12 weeks, decreased symptoms of CRF. Although findings support the safety and effectiveness of ginseng in the treatment of CRF, the number of high-quality studies is not adequate to adopt ginseng as a standard treatment option.
4.3 Cognitive Function
A small amount of research has suggested that Asian ginseng may improve cognitive function, including abstract thinking, attention, arithmetic skills, and reaction time, in middle-aged adults but not in young adults. Any benefit from Asian ginseng on memory has appeared to depend on the addition of ginkgo.
Korean red ginseng extract improved working memory in the psychomotor function study, but there was no effect from Korean red ginseng powder on neurocognitive function tests in healthy subjects. Panax ginseng extract G115 showed no effect on working memory.
According to a systematic review by Lee et al., the evidence of ginseng's efficacy in Alzheimer's disease patients was scarce and inconclusive. A double-blind, controlled clinical trial also reported that there was no improvement in geriatric patients on the performance of the MMSE.
Overall, the evidence for ginseng's effects on cognitive function is preliminary, inconsistent across populations and preparations, and has not yet established clear clinical recommendations.
4.4 Blood Glucose Regulation and Type 2 Diabetes
A 2022 review of 20 studies (1,295 participants) found that Asian ginseng improved many cardiometabolic factors in people with prediabetes and diabetes, including fasting blood glucose levels, total cholesterol, and certain inflammatory markers. But research on the use of Asian ginseng for improving blood sugar control in people with diabetes is overall inconclusive and conflicting.
A meta-analysis included 16 trials, in which 16 fasting blood glucose comparisons (n = 770), 10 fasting plasma insulin comparisons (n = 349), 9 glycated hemoglobin comparisons (n = 264), and 7 HOMA-IR comparisons (n = 305) were reported. Ginseng significantly reduced fasting blood glucose compared to control (MD = −0.31 mmol/L [95% CI: −0.59 to −0.03], P = 0.03). Although there was no significant effect on fasting plasma insulin, glycated hemoglobin, or HOMA-IR, subgroup analyses did show significant reductions in glycated hemoglobin in parallel compared to crossover trials.
The results of another updated systematic review and meta-analysis established the benefit of ginseng supplementation in improving glucose control and insulin sensitivity in patients with type 2 diabetes mellitus or impaired glucose intolerance.
A 2025 randomized controlled trial demonstrated that 90-day supplementation with Korean Ginseng Powder is safe and effective in improving glycemic control, as evidenced by significant reductions in fasting blood glucose, 2-hour postprandial glucose, and HbA1c in patients with type 2 diabetes mellitus and impaired glucose regulation. Despite these individual positive results, the evidence base remains limited by short study durations and heterogeneity of preparations.
4.5 Immune Function
A study in Italy among 227 people found that taking 100 mg of a proprietary Panax ginseng extract (Ginsana G115) once daily for 4 weeks before and 8 weeks after a flu shot stimulated the immune system and reduced cold and flu cases by approximately 65% compared to placebo.
A very small amount of preliminary research suggests that Asian ginseng extract may help reduce the risk of developing the flu but not the severity or duration of symptoms.
Studies using a proprietary American ginseng extract (Cold-FX) suggested it might help prevent the common cold or flu and reduce their duration and severity. However, this was not a standard ginseng extract — it contained a very high concentration of polysaccharides — and there has been criticism of the study designs (most industry-funded) and how results were reported.
Evidence for immune function effects is largely preliminary, with mechanistic support from preclinical studies and a limited number of small clinical trials. It is not sufficient to support clinical recommendations.
4.6 Erectile Dysfunction
Seven RCTs examining red ginseng for erectile dysfunction met inclusion criteria in one systematic review. Their methodological quality was low on average. Six of the included RCTs compared the therapeutic efficacy of red ginseng with placebo. The meta-analysis of these data showed a significant effect (n = 349, risk ratio, 2.40; 95% CI of 1.65, 3.51, p < 0.00001).
Some research shows that taking oral Asian ginseng seems to improve sexual function in people with erectile dysfunction. Possible mechanisms of action of red ginseng include hormonal effects similar to those of testosterone. The overall evidence is considered promising but limited by methodological quality of trials.
4.7 Physical Performance
P. ginseng is the most commonly used as an adaptogenic agent and has been shown to enhance physical performance, promote vitality, increase resistance to stress and aging, and have immunomodulatory activity. However, of 475 potentially relevant studies, 65 met inclusion criteria in a broader systematic review; these examined P. ginseng's effects on psychomotor performance (17 studies), physical performance (10), the circulatory system (8), glucose metabolism (6), the respiratory system (5), erectile dysfunction (4), and immunomodulation (4). The evidence for exercise performance enhancement in healthy individuals from RCTs is mixed and not conclusive.
4.8 Menopausal Symptoms
Ginseng has been used for centuries in traditional medicine to treat various diseases, such as cancer, postmenopausal symptoms, and erectile dysfunction. Clinical evidence for ginseng in managing menopausal symptoms is limited; individual trials report modest benefits, but systematic reviews have found the evidence inconsistent and insufficient to draw firm conclusions.
5. Body Systems and Health Areas
- Central Nervous System: Cognitive function, mental performance, mood, neuroprotection. In vitro and in vivo studies of G115 have shown pharmacological effects on physical performance, cognitive function, metabolism, and the immune system.
- Endocrine/Metabolic System: Blood glucose regulation, insulin sensitivity, cardiometabolic markers.
- Immune System: Enhancement of cellular and humoral immunity, reduction of respiratory infections.
- Cardiovascular System: Ginsenosides appear responsible for vasorelaxation, antioxidation, anti-inflammation.
- Reproductive System: Erectile function.
- Musculoskeletal/Energy Systems: Anti-fatigue effects, physical endurance.
- Oncology (Supportive): Cancer-related fatigue reduction as an adjunct in cancer patients.
6. Dosage Forms and Reported Dosages
The following dosages are drawn from specific clinical studies and reviews as cited in the scientific literature. They represent doses used in research and should not be read as prescriptive recommendations.
- Panax ginseng is available over the counter as whole root, liquid extract, capsule, and powder forms. Ginseng is often taken in doses of 200–400 mg/day, though doses vary based on the preparation.
- Standardized dried root: Studies suggest that using Korean ginseng, the daily intake should be between 0.5 to 2 g of dried root or 100 to 300 mg of a standardized extract that has 1.5% to 7% ginsenosides.
- Cancer-related fatigue — American ginseng: American ginseng, containing more than 5% ginsenosides, consumed at the dosage of 2,000 mg/day for up to eight weeks, significantly reduced fatigue.
- Cancer-related fatigue — Asian ginseng: Asian ginseng, containing ≥ 7% ginsenosides, relieved symptoms of fatigue at the dosage of 400 mg/day in the majority of patients with CRF.
- Cancer-related fatigue — Korean ginseng: Korean ginseng, consumed at the dosage of 3,000 mg/day for 12 weeks, decreased symptoms of CRF.
- Erectile dysfunction: A three-month double-blind, placebo-controlled trial evaluated Korean red ginseng at 1,800 mg/day against trazodone and placebo in 90 men with erectile dysfunction.
- Respiratory infection/immune: 400 mg American ginseng extract daily for four months during cold season and 100 mg of a proprietary Panax ginseng extract (Ginsana G115) once daily for 4 weeks before and 8 weeks after a flu shot were doses used in specific clinical trials.
- Cognitive function (G115): A clinical trial in the Journal of Ethnopharmacology found that when 30 healthy young people each received 200 mg of G115 daily for eight weeks, they improved in attention, processing and reaction time to sound, social skills, and mental health.
- Non-metastatic cancer/fatigue: Patients were randomly divided into two groups; the first group received a daily dose of 100 mg Panax ginseng for 30 days and the second group received placebo medication.
7. Safety Considerations and Drug Interactions
7.1 General Safety Profile
Short-term oral use (up to 6 months) of Asian ginseng in recommended amounts appears to be safe for most people. However, questions have been raised about its long-term safety, and some experts recommend against its use for infants, children, and women who are pregnant or breastfeeding.
The main adverse events of ginseng reported were general symptoms such as hot flushes, insomnia, and dyspepsia, with no significant difference in frequency and symptoms between the ginseng and placebo groups. The symptoms were mild and temporary with no serious or severe adverse events. Panax ginseng showed a very safe profile in a limited number of RCTs with a small number of participants with various conditions.
Patient risks associated with ginseng abuse and misuse include affective disorder, allergy, cardiovascular and renal toxicity, genital organ bleeding, gynecomastia, hepatotoxicity, hypertension, reproductive toxicity, and anticoagulant-ginseng interaction.
7.2 Interaction with Warfarin
Studies on the effect of Asian ginseng on the anticoagulant warfarin have had mixed results. According to Natural Medicines Comprehensive Database, nearly 180 dietary supplements and medicinal herbs are likely to interact with warfarin and ginseng is one of them.
Quality-control ginsenosides, extracted from ginseng and containing its major active ingredients, produce dose- and time-dependent antagonism in rats against warfarin's anti-coagulation assessed by INR and a rat thrombosis model. Studies reviewing the literature regarding the safety and pharmacology of ginseng suggest that ginseng usually tends to cause bleeding. This could be supported by the fact that various types of ginseng inhibit platelet aggregation and prolong blood coagulation time in in vitro and experimental animal studies.
7.3 Interaction with Monoamine Oxidase Inhibitors (MAOIs)
Concomitant use of P. ginseng and the monoamine oxidase inhibitor phenelzine (Nardil) may result in manic-like symptoms.
7.4 Blood Glucose and Hypoglycemia Risk
Given the documented effect of ginseng on blood glucose reduction, Korean red ginseng powder reduced insulin and C-peptide during oral glucose tolerance tests in patients with mild diabetes. Concurrent use with antidiabetic medications may potentiate glucose-lowering effects. Individual variability in response is documented across studies.
7.5 Product Variability
Ginseng products on the market show high variability in their composition and overall quality. This becomes a challenge for both consumers and health-care professionals who are in search of high-quality, reliable ginseng products that have a proven safety and efficacy profile. Differences in preparation method (white vs. red), species, plant part used, and ginsenoside standardization make cross-study comparisons difficult.
7.6 Regulatory Status
Ginseng has not been approved by the US Food and Drug Administration (FDA) to treat or prevent a disease or to provide a health benefit. Traditional uses of ginseng were reaffirmed by the World Health Organization in 1999.
References
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