Ginseng for Energy, Fatigue and Thinking: What Trials Found
What reviews and trials of Panax ginseng and American ginseng found for fatigue, energy, memory and thinking, with the limits and the safety points that matter.
Content last updated . This page has not been medically reviewed.
Safety first. Supplements can cause side effects and interact with medicines. Read mushroom safety and interactions before you use any mushroom product.
Short answer. Trials of Panax ginseng for fatigue and thinking give mixed results. One review of 19 trials found no significant overall drop in fatigue but small benefits in some subgroups, and a Cochrane review found a lack of convincing evidence of a thinking benefit in healthy people. [1][2] Fatigue and trouble concentrating can have medical causes, so a persistent change deserves a clinician's attention before any supplement.
Which ginseng, which part
This page is about Panax ginseng C.A.Mey. (Asian ginseng) and Panax quinquefolius L. (American ginseng), both in the family Araliaceae. [3] The root is the part most often used. [4] Siberian ginseng (eleuthero) and "Indian ginseng" (ashwagandha) are different plants; see ginseng types compared. "Adaptogen" is a contested label; see what adaptogens are.Traditional use and promotion (not proof)
Traditional use. NIH says Asian ginseng has been used as a calming agent in traditional Chinese medicine and as an adaptogen. [4] See ginseng in Chinese medicine for the tradition.Marketing. NIH notes it has been promoted for stress, cognitive function, flu, fatigue, athletic performance, diabetes, aging, asthma, anxiety and other conditions. [4] Promotion is not evidence.
What trials and reviews found
| Question | What the source found | Strength of evidence | Population and form |
|---|---|---|---|
| Fatigue, all trials pooled | No significant reduction in fatigue severity versus controls overall; a significant reduction in general (non-disease) fatigue; effect sizes were small. [1] | Mixed | 19 randomized trials; different ginseng types and formulas |
| Fatigue with herbal formulas | NIH describes a 2023 review of 19 studies: certain ginseng formulas with other ingredients may be beneficial for chronic fatigue, but not ginseng alone. [4] | Promising but limited | Formulas, not single ginseng |
| Cancer-related fatigue (American ginseng) | At 4 weeks the difference was not statistically significant (P = .07); at 8 weeks it was. Toxicities did not differ from placebo. [5] | Promising but limited | 364 fatigued cancer survivors; 2000 mg a day; 8 weeks |
| Cancer-related fatigue (reviews and a newer trial) | A review of 12 studies reported benefit, but it combined oral ginseng with ginseng injections. [6] A 4-week trial of a Panax ginseng extract in 65 gastrointestinal cancer survivors reported lower fatigue and no treatment-related adverse events. [7] | Promising but limited | Survivors; oral extract 250 mg a day in the newer trial |
| Fatigue in healthy adults | A red ginseng extract lowered a fatigue rating scale versus placebo, but not blood lactic acid or cortisol. [8] | Promising but limited | 46 healthy middle-aged Japanese adults; 960 mg; 3 weeks |
| Fatigue in rheumatic disease | No clear benefit: 38.3% vs 26.7% improved, not statistically significant. [9] | No good evidence of benefit | 120 patients; 2 g a day of red ginseng; 12 weeks |
| Thinking in healthy adults | The Cochrane review found a lack of convincing evidence of a cognitive-enhancing effect of Panax ginseng in healthy participants, and no high-quality evidence in dementia. [2] | Insufficient evidence | 9 trials, 5 analyzed |
| Memory and thinking (newer pooling) | Memory improved slightly (SMD 0.19), but not overall cognition, attention or executive function. [10] | Mixed | 15 trials; 671 people; healthy and unwell groups pooled |
| Thinking by age (NIH) | A small amount of research suggests improved cognition in middle-aged but not young adults; any memory benefit appeared to depend on adding ginkgo. [4] | Promising but limited | Small trials |
| Athletic performance | The majority of research shows Asian ginseng does not improve it. [4] | No good evidence of benefit | Various |
Frequently asked questions
Does ginseng give you energy?
The evidence is mixed. A review of 19 trials found no significant reduction in fatigue overall, with a significant benefit for general fatigue and small effect sizes. [1] NIH says not all research agrees on benefits for fatigue. [4]
Does ginseng improve memory or focus?
A pooled analysis of 15 trials found a small memory effect but no effect on overall cognition or attention. [10] The Cochrane review found a lack of convincing evidence in healthy people. [2]
Is American ginseng better than Asian ginseng for fatigue?
Proper evidence not found. We searched PubMed and NIH pages; the larger American ginseng trial was in cancer survivors, [5] and no head-to-head trial was in the sources we read.
Can ginseng cause trouble sleeping?
Yes. NIH says insomnia is its most common side effect. [4]
What amount works?
We cannot give a personal amount. Trials used different amounts, for example 250 mg a day for four weeks in one extract trial [7] and 2000 mg a day for eight weeks in another. [5] A clinician or pharmacist decides what is right for a person.
More details: evidence, limits and cautions
The details behind this page: cautions, limits of the evidence and where sources disagree. Open any note to read it.
Limits and uncertainty
- NIH says most Asian ginseng trials have been small, with fewer than 200 participants, and shorter than 3 months. [4]
- Results are for particular extracts, amounts and groups. A result in cancer survivors, in healthy students or from an injection does not transfer to a capsule in a different person.
- Fatigue scales are self-reported, and a lab marker such as cortisol or lactic acid is not the same as feeling less tired. In the healthy-adult trial the scale changed but the lab markers did not. [8]
- Funding and conflicts of interest: not described in the abstracts we read.
Safety: who should ask first
Other reading: Asian ginseng, American ginseng, energy and fatigue, energy supplements compared and fatigue: when to get help.
References
- Li X, Yang M, Zhang YL, et al. Ginseng and ginseng herbal formulas for symptomatic management of fatigue: a systematic review and meta-analysis. J Integr Complement Med. 2023. PubMed 36730693. Read 2026-10-23.
- Geng J, Dong J, Ni H, et al. Ginseng for cognition. Cochrane Database Syst Rev. 2010. PubMed 21154383. Read 2026-10-23.
- GBIF Secretariat. GBIF Backbone Taxonomy. Names checked through the species match API on 2026-10-23.
- National Center for Complementary and Integrative Health (NIH). Asian Ginseng: Usefulness and Safety. Read 2026-10-23.
- 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. PubMed 23853057. Read 2026-10-23.
- Li H, et al. Efficacy of ginseng oral administration and ginseng injections on cancer-related fatigue: a meta-analysis. Medicine (Baltimore). 2022. PubMed 36401389. Read 2026-10-23.
- Rahmani A, et al. The effect of ginseng extract on fatigue in cancer survivors: a randomized double-blind clinical trial. Support Care Cancer. 2026. PubMed 41838185. Read 2026-10-23.
- Lee YG, et al. Anti-fatigue effects of Korean Red Ginseng extract in healthy Japanese adults: a randomized, double-blind, placebo-controlled study. J Ginseng Res. 2025. PubMed 40453352. Read 2026-10-23.
- Cho SK, et al. Effectiveness of Korean Red Ginseng on fatigue in patients with rheumatic diseases: a randomized, double-blind, placebo-controlled study. Korean J Intern Med. 2024. PubMed 38576235. Read 2026-10-23.
- Zeng M, et al. Effects of ginseng on cognitive function: a systematic review and meta-analysis. Phytother Res. 2024. PubMed 39474788. Read 2026-10-23.
- Bostock EC, Kirkby KC, Taylor BV, Hawrelak JA. Mania associated with herbal medicines, other than cannabis: a systematic review and quality assessment of case reports. Front Psychiatry. 2018. PubMed 30034348. Read 2026-10-23.
- Norelli LJ, Bernstein BE, Stubbs JB. Manic psychosis associated with ginseng: a report of two cases and discussion of the literature. J Diet Suppl. 2015. PubMed 24689505. Read 2026-10-23.
- Elvir Lazo OL, et al. Use of herbal medication in the perioperative period: potential adverse drug interactions. J Clin Anesth. 2024. PubMed 38613937. Read 2026-10-23.