How to Take Ginseng: Dosage, Timing and Duration
Ginseng is one of the oldest and best-studied herbal products, sold in the UK as a food supplement and as licensed traditional herbal medicines. Its results depend heavily on choosing the right type, taking a dose that matches the research and using it for a sensible length of time. Our editorial team explains how to take ginseng properly.
Which ginseng are you buying?
The word ‘ginseng’ covers several different plants. Asian or Korean ginseng (Panax ginseng) is the most researched and is traditionally regarded as more stimulating. American ginseng (Panax quinquefolius) is often described as gentler and has been studied for its effects on blood glucose.
Siberian ginseng (Eleutherococcus senticosus) is not a true ginseng at all. It belongs to the same plant family but contains different active compounds, eleutherosides rather than ginsenosides, so results from Panax studies cannot be applied to it.
The active constituents of Panax species are ginsenosides, and their content varies with the plant part, age of the root and processing. ‘Red’ ginseng is steamed and dried, which changes its ginsenoside profile, while ‘white’ ginseng is simply dried.
In the UK, look for products with a Traditional Herbal Registration (THR) mark from the MHRA, or supplements that state a standardised ginsenoside content. These offer more consistency than unspecified ‘ginseng root powder’.
Dosage: what the studies used
Unlike licensed drugs, ginseng has no single official dose, but the clinical literature points to fairly consistent ranges. Doses depend on whether you take a standardised extract or dried root.
| Form | Amounts typically studied per day | Notes |
|---|---|---|
| Standardised Panax ginseng extract (e.g. G115) | 200–400 mg | Most cognitive and fatigue studies |
| Dried Panax ginseng root | About 1–2 g | Matches traditional use and EMA monograph ranges |
| American ginseng | About 1–3 g of root | Studied for post-meal glucose |
| Red ginseng extract | As per label; often 1–3 g | Ginsenoside content varies |
Kennedy and Scholey’s research group used single doses of 200–400 mg of standardised extract and observed changes in mental performance and blood glucose within hours. Interestingly, higher doses were not always better.
A sensible approach is to begin at the lower end of the range, follow the label of a reputable product, and only increase if well tolerated. Combining several ginseng-containing products, such as an energy drink plus a capsule, makes the total intake hard to judge.
Results from meta-analyses, including that by Bach and colleagues on fatigue and physical performance, are mixed. Ginseng may help some people with fatigue, but its effect on strength or endurance in trained athletes is not convincingly established, as Bahrke and Morgan noted in their review.
Best time of day to take it
Panax ginseng can be mildly stimulating, so most practitioners recommend taking it in the morning or early afternoon. Taking it late in the day may disturb sleep in sensitive people.
Taking ginseng with breakfast or lunch reduces the chance of stomach upset. Because American ginseng can lower blood glucose after meals, Vuksan and colleagues tested it shortly before eating; people prone to low blood sugar should take it with food.
For a training-day routine, there is no strong evidence that taking ginseng immediately before exercise is better than taking it with breakfast. Consistency matters more than exact timing for any potential longer-term effects.
If you already use caffeine before training, introduce ginseng separately first so you can tell which product is responsible for any jitteriness, palpitations or sleep problems.
How long to take ginseng
The European Medicines Agency’s herbal monograph and many THR leaflets advise using ginseng for a limited period, commonly up to three months, and to consult a doctor if symptoms persist. Many people prefer cycles of several weeks followed by a break.
There is no solid evidence that breaks prevent ‘tolerance’, but they provide a natural point to judge whether the supplement is genuinely helping. Keeping a short diary of energy, sleep and training quality makes this easier.
Useful questions at the end of a course include:
- Has my energy or concentration noticeably changed?
- Have I had any side effects such as poor sleep, headaches or digestive upset?
- Have my medicines or health conditions changed?
- Is the cost justified by the benefit I perceive?
Side effects, interactions and who should avoid it
Ginseng is generally well tolerated in studies. Reported side effects include insomnia, headache, nervousness, digestive upset and, less often, changes in blood pressure. These are more likely at higher doses or with stimulant combinations.
Interactions are more important. A randomised trial by Yuan and colleagues found that American ginseng reduced the anticoagulant effect of warfarin. Ginseng may also add to the effects of diabetes medicines, and theoretical interactions exist with MAO inhibitors and stimulants.
Groups who should avoid ginseng or check with a doctor include pregnant and breastfeeding women, children, people with uncontrolled high blood pressure, those taking anticoagulants or diabetes medicines and people with hormone-sensitive conditions, since some ginsenosides may have weak oestrogen-like effects.
Ginseng is not on the WADA prohibited list, but athletes should choose batch-tested products, as herbal supplements have occasionally been found contaminated with stimulants.
Editorial conclusions
Choose the right plant: Panax ginseng and American ginseng are distinct, and Siberian ginseng is not a true ginseng at all.
Studies typically use 200–400 mg of standardised extract or roughly 1–2 g of dried root daily, taken in the morning or early afternoon with food.
Use ginseng in defined courses of up to about three months, review the benefit and check for interactions, especially with warfarin and diabetes medicines.
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References
- Bach HV, Kim J, Myung SK, Cho YA. Efficacy of ginseng supplements on fatigue and physical performance: a meta-analysis. J Korean Med Sci. 2016;31(12):1879–1886.
- Bahrke MS, Morgan WP. Evaluation of the ergogenic properties of ginseng: an update. Sports Med. 2000;30(2):113–133.
- Kennedy DO, Scholey AB. Ginseng: potential for the enhancement of cognitive performance and mood. Pharmacol Biochem Behav. 2003;75(3):687–700.
- Reay JL, Kennedy DO, Scholey AB. Single doses of Panax ginseng (G115) reduce blood glucose levels and improve cognitive performance during sustained mental activity. J Psychopharmacol. 2005;19(4):357–365.
- Vuksan V, Sievenpiper JL, Koo VY, 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(7):1009–1013.
- Yuan CS, Wei G, Dey L, et al. Brief communication: American ginseng reduces warfarin's effect in healthy patients: a randomized, controlled trial. Ann Intern Med. 2004;141(1):23–27.
- European Medicines Agency, Committee on Herbal Medicinal Products. Community herbal monograph on Panax ginseng C.A. Meyer, radix. London: EMA; 2014.
