Ginseng is usually derived from two different species of plant: American ginseng and Asian ginseng. American ginseng is milder than Asian ginseng. Ginseng is available in many forms, such as fresh and dried roots, extracts, solutions, capsules, tablets, cosmetics, sodas, and teas. The active components are panaxosides in American ginseng and ginsenosides in Asian ginseng.
Siberian ginseng is not really ginseng and contains different active components.
Ginseng products vary considerably in quality because many contain little or no detectable active ingredient. In very few cases, some ginseng products from Asia have been purposefully mixed with mandrake root, which has been used to induce vomiting, or with phenylbutazone or aminopyrine—drugs that have been removed from the market in the United States because of unacceptable side effects.
(See also Overview of Dietary Supplements.)
People take ginseng mostly to enhance physical and mental performance and to increase energy and resistance to the harmful effects of stress and aging. There is no convincing evidence that ginseng enhances mental performance in either healthy people or those diagnosed with dementia. Many take it to enhance sexual performance, including treating erectile dysfunction. Ginseng may reduce blood sugar levels and increase levels of high-density lipoprotein (HDL)—the good—cholesterol. Ginseng may also improve immune function. One study found that it did not prevent colds but did shorten their duration.
Evaluating some of ginseng’s effects is difficult because measuring an increase in energy and other quality-of-life effects is difficult. In one study of people with diabetes, ginseng reduced blood sugar levels and, according to a subjective report, improved mood and energy. In one large but short study, ginseng improved quality of life, according to a subjective report.
Ginseng has a reasonably good safety record. However, some authorities recommend limiting the use of ginseng to 3 months because of the possible development of side effects. The most common side effects are nervousness and excitability, which usually decrease after the first few days. The ability to concentrate may be decreased, and blood sugar may decrease to abnormally low levels (causing hypoglycemia). Other side effects may include headaches, allergic reactions, and sleep and digestive problems, breast tenderness, and menstrual irregularities. Because ginseng has an estrogen-like effect, women who are pregnant or breastfeeding should not take it, nor should children.
Occasionally, there have been reports of more serious side effects, such as asthma attacks, increased blood pressure, palpitations, and, in postmenopausal women, uterine bleeding. To many people, ginseng tastes unpleasant.
Ginseng can interact with drugs that prevent blood clots, aspirin, other nonsteroidal anti-inflammatory drugs (NSAIDs), corticosteroids, digoxin, estrogen therapy, monoamine oxidase inhibitors (MAOIs, used to treat depression), and drugs that decrease blood sugar levels (hypoglycemic drugs, used to treat diabetes).
The following is an English-language resource that may be useful. Please note that THE MANUAL is not responsible for the content of this resource.
National Institutes of Health (NIH), National Center for Complementary and Integrative Health: General information on the use of Asian ginseng as a dietary supplement