Ginseng (Panax ginseng): what the evidence says and how to use it safely

The ginseng sold in UK health shops usually means the dried root of Panax ginseng. A different plant, Siberian ginseng, is a distinct species with a separate research record, so a label that only says ginseng does not tell you which one you are getting. The botanical name on the pack matters.

The root is prepared in two main ways. White ginseng is dried, while red ginseng is steamed first. Both are the same plant. Products range from whole-root powders to concentrated extracts, and the amount of the active ginsenoside compounds can differ a good deal between brands, which is one reason trial results do not translate neatly into a shop-bought tablet.

The US National Center for Complementary and Integrative Health summarises the evidence as modest. Some studies suggest improved abstract thinking, attention and arithmetic in middle-aged adults. A 2023 review suggested a small beneficial effect on general fatigue when ginseng was used on its own, and there are signs that regular use may reduce the chance of catching flu, although not how severe the illness is.

In men with erectile dysfunction, some trials point to better sexual function. Anyone with persistent erection difficulty should still see their GP, because it can be an early marker of heart disease, diabetes or low testosterone, and effective licensed treatments exist.

• Blood sugar: research is inconclusive and conflicting, so ginseng should not be treated as a diabetes remedy.

• Sport: the majority of studies show no performance benefit.

• Long-term effects: evidence is much thinner beyond short courses.

Insomnia is the usual complaint, which is why many people who try ginseng take it in the morning rather than late in the day. Less often, severe skin rash, liver injury and serious allergic reactions have been reported. Ginseng may also make autoimmune disorders worse, so people with conditions such as lupus or rheumatoid arthritis should speak to their specialist first.

Short-term oral use for up to six months looks acceptable for most adults, but nobody knows whether it is safe over longer periods. Stop the product and seek medical advice if you develop a rash, swelling of the face or lips, yellowing of the skin or eyes, or dark urine.

Ginseng may lower blood sugar. A person on insulin, gliclazide or similar tablets could therefore be pushed towards hypoglycaemia, with sweating, shakiness and confusion. If you have diabetes, tell your diabetes team before starting it and check your readings more often.

It may also affect blood clotting, which is a particular concern alongside warfarin, a DOAC, aspirin or clopidogrel. The NHS advises checking with a pharmacist before taking a herbal medicine if you already take other medicines, and it lists blood thinners, diabetes drugs, blood-pressure medicines, antidepressants and hormonal contraceptives among the groups where interactions occur.

Some studies suggest oral ginseng may be unsafe in pregnancy, with a possible risk of birth defects, and there is little safety information for breastfeeding. The NHS position on herbal medicines is cautious: they are not recommended in pregnancy or breastfeeding, and are not recommended for children because safety data are lacking.

Most ginseng products on sale here are food supplements, which are not tested for effectiveness in the way a medicine is. A smaller number are registered under the Traditional Herbal Registration scheme run by the MHRA. A product carrying the THR mark has been assessed for acceptable safety, manufacturing quality and accurate patient information, but the MHRA does not assess whether it works, because the approved use rests on traditional use.

The MHRA has warned that most herbal medicines on the UK market are unlicensed and that quality varies. The NHS advises against buying unlicensed herbal medicines online. Look for the THR mark and the product code on the pack, and report suspected side effects through the Yellow Card scheme.

Choose a product that names the plant species and the part used, take it for a defined trial period rather than indefinitely, and keep a note of whether anything changes. If persistent tiredness is the reason, ask your GP about blood tests first, because tiredness has many medical causes, including anaemia, thyroid problems, low mood and sleep apnoea.