Ginseng has been used in Chinese medicine for thousands of years. The name "ginseng" refers to both American (Panax quinquefolius) and Asian or Korean ginseng (Panax ginseng), which are made up of similar chemicals. Siberian ginseng, or Eleuthero (Eleutherococcus senticosus), is a completely different plant and does not have the same active ingredients. Both Asian and American ginseng contain substances called ginsenosides, which researchers think are the active ingredients.

Like American ginseng, Asian ginseng is a gnarled root that looks like a human body with stringy shoots for arms and legs. Long ago, herbalists thought that because of the way ginseng looks it could treat many problems, from fatigue and stress to asthma and cancer. In traditional Chinese medicine (TCM), ginseng is often combined with other herbs.

Today, ginseng is sometimes called an "adaptogen," which is a substance that is supposed to help the body better cope with mental or physical stress. Scientists have not found any evidence that adaptogens exist. But ginseng has been studied for several conditions, and it is one of the most popular herbs in the United States.

Many studies of Asian or Korean ginseng have used combinations of herbs. So it is not always possible to say whether ginseng by itself produced the results. Research on Asian ginseng has included the following conditions:

Cold and flu

It has been said that Asian ginseng boosts the immune system, which might help the body fight off infection and disease. The best evidence is that it may help reduce your risk of getting a cold or flu. Studies have found that ginseng seems to increase the number of immune cells in the blood and improve the immune system's response to a flu vaccine. In one study, 227 people got either ginseng or placebo for 12 weeks, and got a flu vaccine after 4 weeks. The number of colds and flu were two-thirds lower in the group that took ginseng.

Two studies found that ginseng lowered the chance of getting a cold. In one double-blind, placebo-controlled study of 323 people, those who took 400 mg of ginseng daily for 4 months had fewer colds. When they did get a cold, it was less severe and shorter than the colds of people who took placebo.

Heart health

Asian ginseng seems to be an antioxidant. Antioxidants help rid the body of free radicals, which are substances that can damage DNA and contribute to heart disease, diabetes, and other conditions. Preliminary studies suggest Asian ginseng may improve the symptoms of heart disease in people. It also may decrease LDL (bad) cholesterol levels and raise HDL (good) cholesterol.

Asian ginseng's effect on blood pressure is more complicated. Some studies suggest it lowers blood pressure while others found that it causes blood pressure to rise. This has led researchers to question if ginseng increases blood pressure at usual doses, but lowers it when doses are higher. Until researchers know for sure, you should not take ginseng if you have high blood pressure unless your doctor tells you it is OK.

Type 2 diabetes

Although American ginseng has been studied more for diabetes, both types of Panax ginsengs may lower blood sugar levels in people with type 2 diabetes. However, in a few studies it looked like Asian or Korean ginseng raised blood sugar levels. Some people think that the ginsenosides in American ginseng might lower blood sugar while different ginsenosides in Asian ginseng could raise blood sugar levels. Until researchers know more, you should not take ginseng if you have diabetes without your doctor's supervision and monitoring.

Mental performance

People who take ginseng often say they feel more alert. Several studies report that Asian ginseng may slightly improve thinking or learning. Early research shows that Asian ginseng may improve performance on such things as mental arithmetic, concentration, memory, and other measures. Some studies have also found a positive effect with the combination of Asian ginseng and Ginkgo biloba.

Most of the studies have found that ginseng does improve mental performance. But they have measured different kinds of mental function. That makes it hard to know exactly what the effects of ginseng are. For example, one study found that people who took ginseng increased their ability for abstract thought. But it did not create any changes in their reaction time or concentration levels.

Physical endurance

There have been a number of studies using Asian ginseng for athletic performance in people and laboratory animals. Results have been mixed, with some studies showing better strength and endurance, others showing improved agility or reaction time, and others showing no effect at all. Even so, athletes often take Asian ginseng to boost both endurance and strength. Asian ginseng was also found to reduce fatigue in a study of 332 people.

Stress and well-being

Asian ginseng is sometimes credited with helping the body deal with physical or mental stress. While these properties can be difficult to study, there is some evidence that ginseng (both Asian and American) can improve quality of life, although quality of life can be hard to measure, too.

A study of 501 men and women living in Mexico City found better quality of life measures (energy, sleep, sex life, personal satisfaction, and well-being) in those taking Asian ginseng. Another well-designed study found that people who took a nutritional supplement with ginseng said they had better quality of life than those taking the same supplement without ginseng.

Fertility/erectile dysfunction

Asian ginseng is widely believed to boost sexual performance. But there are not many studies to back this up. In animal studies, Asian ginseng has increased sperm production, sexual activity, and sexual performance. A study of 46 men has also shown an increase in sperm count as well as motility. Another study in 60 men found that Asian ginseng increased sex drive and decreased erection problems. Also, in one study of 45 men, those who took 900 mg of Korean ginseng 3 times per day for 8 weeks had less trouble getting an erection than those who took placebo.

Cancer

Several studies suggest that Asian ginseng may reduce the risk of some types of cancers. In one observational study, researchers followed 4,634 people for 5 years. They found that those who took ginseng had lower risks of lung, liver, pancreatic, ovarian, and stomach cancers. But the study could not be sure that other things, including healthy eating habits, were responsible for the lower risk of cancer. The study also found that taking ginseng only 3 times a year led to a big reduction in cancer risk.

Several studies suggest that Asian ginseng slows down or stops the growth of tumors, although researchers are not yet sure how it might work in humans. More research is needed.

Menopausal symptoms

There have been only a few studies of ginseng for menopausal symptoms. Two well-designed studies evaluating red Korean (Asian) ginseng suggest it may relieve some of the symptoms of menopause, improving sense of well-being and mood, particularly feelings of depression. People took ginseng along with a vitamin and mineral supplement. Other studies show no effect.

The ginseng plant has leaves that grow in a circle around a straight stem. Yellowish-green, umbrella-shaped flowers grow in the center and produce red berries. Ginseng has a taproot that looks a little like the human body, with 2 "arms" and 2 "legs." Wrinkles around the neck of the root tell how old the plant is. Ginseng is not ready to be used as medicine until it has grown for about 6 years.

Asian or Chinese and Korean ginseng are the same plants, but grown in different areas. American ginseng is a relative of the same species, native to North America.

Asian ginseng supplements are made from the ginseng root, and the long, thin offshoots, called root hairs. Both Asian or Korean and American ginseng have ginsenosides, saponins that are ginseng's active ingredients. Asian ginseng also contains glycans (panaxans), polysaccharide fraction DPG-3-2, peptides, maltol, B vitamins, flavonoids, and volatile oil.

White ginseng (dried, peeled) or red ginseng (unpeeled root, steamed before drying) is available in water, water-and-alcohol, or alcohol liquid extracts, and in powders or capsules. Asian ginseng root is also available for making decoctions (boiling the root in water).

Read the label carefully to make sure you get the type of ginseng you want. If you are looking for Asian ginseng, make sure you buy Korean, red, or Panax ginseng. If you are looking for American ginseng, you should buy Panax quinquefolius. Eleuthero (Eleutherococcus senticosus), which is sometimes called Siberian ginseng, does not have the same active ingredients as Asian or American ginseng.

Pediatric

Do not give ginseng to a child.

Adult

Asian ginseng comes in different forms and is often used in combination with other herbs or nutrients. Talk with an experienced health care practitioner to find the right dose for you.

Healthy people who want to boost physical or mental performance, prevent illness, or better resist stress should take Asian ginseng in cycles. For example, take every day for 2 to 3 weeks, then stop for 3 weeks, then start back.

The use of herbs is a time-honored approach to strengthening the body and treating disease. However, herbs can trigger side effects and interact with other herbs, supplements, or medications. For these reasons, you should take herbs with care under the supervision of a health care provider, qualified in the field of botanical medicine.

Asian ginseng should not be taken continuously; take periodic breaks and consult a trained herbal prescriber if you are considering long-term use.

Asian ginseng may cause nervousness or sleeplessness, especially if taken at high doses or combined with caffeine. Other side effects are rare, but may include:

• High blood pressure
• Insomnia
• Restlessness
• Anxiety
• Euphoria
• Diarrhea
• Vomiting
• Headache
• Nose bleed
• Breast pain
• Vaginal bleeding

To avoid hypoglycemia or low blood sugar, even in people without diabetes, take Asian ginseng with food.

People with high blood pressure should not take Asian ginseng products without their doctor's supervision. People who are ill or have low blood pressure should take caution when using Asian ginseng.

People with bipolar disorder should not take ginseng because it may increase the risk of mania.

People with an autoimmune disease, such as rheumatoid arthritis, lupus, or Crohn disease, should ask their doctors before taking Asian ginseng. Theoretically, Asian ginseng may boost an already overactive immune system.

Pregnant or breastfeeding women should not take Asian ginseng. Asian ginseng may cause vaginal bleeding.

Women who have a history of breast cancer should not take ginseng.

Stop taking Asian ginseng at least 7 days prior to surgery. Asian ginseng may act as a blood thinner, increasing the risk of bleeding during or after a procedure.

If you are currently taking any of the following medications, you should not use Asian ginseng without first talking to your health care provider:

ACE inhibitors (blood pressure medications): Asian ginseng may interact with angiotensin-converting enzyme (ACE) inhibitors used to lower high blood pressure. These medications include:

• Captopril (Capoten)
• Benazepril (Lotensin)
• Enalapril (Vasotec)
• Lisinopril (Prinivil, Zestril)
• Fosinopril (Monopril)
• Ramipril (Altace)
• Perindopril (Aceon)
• Quinapril (Accupril)
• Moexipril (Univasc)
• Trandolapril (Mavik)

Calcium channel blockers (heart and blood pressure medications): Asian ginseng may make certain heart medications, including calcium channel blockers, work differently than intended. These medications include:

• Amlodipine (Norvasc)
• Diltiazem (Cardizem)
• Nifedipine (Procardia)

Blood-thinners (anticoagulants and antiplatelets): Asian ginseng may increase the risk of bleeding, especially if you already take blood thinners, such as aspirin, warfarin (Coumadin), or clopidogrel (Plavix).

Caffeine: Ginseng may make the effect of caffeine stronger, possibly causing nervousness, sweating, insomnia, or irregular heartbeat.

Diabetes medications, including insulin: Ginseng may lower blood sugar levels, increasing the risk of hypoglycemia or low blood sugar.

Drugs that suppress the immune system: Asian ginseng may boost the immune system and may interact with drugs taken to treat an autoimmune disease or drugs taken after organ transplant.

Stimulants: Ginseng may increase the stimulant effect and side effects of some medications taken for attention deficit hyperactivity disorder (ADHD), including amphetamine and dextroamphetamine (Adderall) and methylphenidate (Concerta, Ritalin).

MAOIs (monoamine oxidase inhibitors): Ginseng may increase the risk of mania when taken with MAOIs, a kind of antidepressant. There have been reports of interaction between ginseng and phenelzine (Nardil) causing headaches, tremors, and mania. MAOIs include:

• Isocarboxazid (Marplan)
• Phenelzine (Nardil)
• Tranylcypromine (Parnate)

Morphine: Asian ginseng may block the painkilling effects of morphine.

Furosemide (Lasix): Some researchers think Asian ginseng may interfere with Lasix, a diuretic (water pill) that helps the body get rid of excess fluid.

Other medications: Asian ginseng may interact with medications that are broken down by the liver. To be safe, if you take any medications, ask your doctor before taking Asian ginseng.

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