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American ginseng (Panax quinquefolis) is an herb that grows mainly in North America. Wild American ginseng is in such high demand that it has been declared a threatened or endangered species in some states in the United States.
People take American ginseng by mouth for stress, to boost the immune system, and as a stimulant.
American ginseng is used for other infections including HIV/AIDS, infections of the intestine (dysentery), and particular infections (Pseudomonas infections) that are common in people with cystic fibrosis.
Some people use American ginseng to improve digestion and for loss of appetite, as well as for vomiting, inflammation of the colon (colitis), and inflammation of the lining of the stomach (gastritis).
American ginseng is also used for low iron in the blood (anemia), diabetes, insulin resistance related to HIV treatments, cancer-related fatigue, high blood pressure, trouble sleeping (insomnia), nerve pain, erectile dysfunction (ED), fever, hangover symptoms, attention deficit-hyperactivity disorder (ADHD), blood and bleeding disorders, breast cancer, dizziness, headaches, convulsions, fibromyalgia, "hardening of the arteries" (atherosclerosis), memory loss, rheumatoid arthritis, schizophrenia, improving athletic performance, improving mental performance, as an anti-aging aid, menopausal symptoms, complications during pregnancy or childbirth, and for nervous exhaustion (neurasthenia).
Don't confuse American ginseng with Siberian ginseng (Eleutherococcus senticosus) or Asian ginseng (Panax ginseng). They have different medicinal effects.
How does it work?
American ginseng contains chemicals called ginsenosides that seem to affect insulin levels in the body and lower blood sugar. Other chemicals, called polysaccharides, might affect the immune system.
Possibly Effective for...
- Diabetes. Taking 3 grams of American ginseng by mouth, up to two hours before a meal, can lower blood sugar after a meal in patients with type 2 diabetes. However, larger doses do not seem to have a greater effect. Taking 100-200 mg of American ginseng by mouth for 8 weeks might also help lower pre-meal blood sugar levels in patients with type 2 diabetes. Different American ginseng products may have different effects. Researchers think that is because they contain different amounts of the active chemicals called ginsenosides.
- Respiratory tract infections. Some research suggests that taking a specific American ginseng extract called CVT-E002 (Cold-FX, Afexa Life Sciences, Canada) 200-400 mg twice daily for 3-6 months during flu season might prevent cold or flu symptoms in adults between the ages of 18 and 65. People older than 65 seem to need a flu shot at month 2 along with this treatment in order to decrease their risk of getting the flu or colds. This extract also seems to help make symptoms milder and last a shorter length of time when infections do occur. Some evidence suggests that the extract might not reduce the chance of getting the first cold of a season, but it seems to reduce the risk of getting repeat colds in a season. However, it might not help prevent cold or flu-like symptoms in patients with weakened immune systems.
Possibly Ineffective for...
- Athletic performance. Taking 1600 mg of American ginseng by mouth for 4 weeks does not seem to improve athletic performance. But it might decrease muscle damage during exercise.
Insufficient Evidence to Rate Effectiveness for...
- Insulin resistance caused by HIV treatment. Early research shows that taking capsules containing 1 gram of American ginseng root three times daily for 14 days while receiving the drug indinavir, which is a type of HIV therapy, does not reduce insulin resistance caused by indinavir in healthy people.
- Attention deficit-hyperactivity disorder (ADHD). There is early evidence that a specific product (AD-fX, Afexa Life Sciences, Canada) containing American ginseng extract in combination with ginkgo leaf extract might help improve ADHD symptoms such as anxiety, hyperactivity, and impulsiveness in children aged 3-17 years.
- Breast cancer. Some studies conducted in China suggest that breast cancer patients treated with any form of ginseng (American or Panax) do better and feel better. However, this may not be a result of taking the ginseng, because the patients in the study were also more likely to be treated with the prescription cancer drug tamoxifen. It is difficult to know how much of the benefit to attribute to ginseng.
- Cancer-related fatigue. Research on the effects of American ginseng in people with fatigue related to cancer is not consistent. One study shows that taking 700-2000 mg of American ginseng daily for 8 weeks does not reduce fatigue in people with cancer. However, other research shows that taking 2000 mg of American ginseng in two doses daily for 8 weeks reduces fatigue by 51%. The conflicting results might be due to the different methods used to measure fatigue in the studies.
- Mental performance. Some research suggests that taking one 100-400 mg dose of American ginseng (Cereboost, Naturex) 1-6 hours before mental tests improves short-term memory and reaction time in healthy people.
- High blood pressure. Evidence on the effects of American ginseng in people with high blood pressure is not consistent. Some research shows that taking 1500 mg of American ginseng twice daily for 12 weeks does not reduce blood pressure. But other research shows that taking 1000 mg of American ginseng extract three times daily for 12 weeks lowers blood pressure in people with diabetes and high blood pressure. The differences in the research might be related to the amount of ginsenosides, the active chemical in American ginseng, that is contained in the products used.
- Menopausal symptoms. Early research suggests that taking a product containing American ginseng, black cohosh, dong quai, milk thistle, red clover, and vitex agnus-castus (Phyto-Female Complex, SupHerb, Netanya, Israel) twice daily for 3 months reduces menopausal symptoms, including hot flashes, night sweats, and sleep quality. However, it is not clear if these effects are caused by American ginseng or the other ingredients in the product.
- Schizophrenia. Early research shows that American ginseng might improve some mental symptoms associated with schizophrenia. Taking 100 mg of a specific American ginseng extract called HT1001 (Afexa Life Sciences, Canada) twice daily for 4 weeks improves the patient's ability to hold visual information in the mind short-term. This treatment might also reduce some physical side effects of antipsychotic drugs. However, it does not improve other mental symptoms.
- Bleeding disorders.
- Digestive disorders.
- Hangover symptoms.
- Memory loss.
- Nerve pain.
- Pregnancy and childbirth complications.
- Rheumatoid arthritis.
- Swine flu.
- Other conditions.
Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, and Insufficient Evidence to Rate (detailed description of each of the ratings).
American ginseng is LIKELY SAFE when taken by mouth appropriately, short-term. Doses of 100-3000 mg daily have been used safely for up to 12 weeks. Single doses of up to 10 grams have also been safely used. In addition, a specific American ginseng extract called CVT-E002 (Cold-FX, Afexa Life Sciences, Canada) has also been used safely for up to 6 months.
When taken by mouth, American ginseng can cause some side effects including diarrhea, itching, trouble sleeping (insomnia), headache, and nervousness. In some people, American ginseng might also cause rapid heartbeat, increased blood pressure or decreased blood pressure, breast tenderness, vaginal bleeding in women, and other side effects. Uncommon side effects that have been reported include a severe rash called Stevens-Johnson syndrome, liver damage, and severe allergic reaction.
Pregnancy and breast-feeding: American ginseng is POSSIBLY UNSAFE in pregnancy. One of the chemicals in Panax ginseng, a plant related to American ginseng, has been linked to possible birth defects. Do not take American ginseng if you are pregnant.
There is not enough reliable information about the safety of taking American ginseng if you are breast feeding. Stay on the safe side and avoid use.
Diabetes: American ginseng might lower blood sugar. In people with diabetes who are taking medications to lower blood sugar, adding American ginseng might lower it too much. Monitor your blood sugar closely if you have diabetes and use American ginseng.
Hormone-sensitive conditions such as breast cancer, uterine cancer, ovarian cancer, endometriosis, or uterine fibroids: American ginseng preparations that contain chemicals called ginsenosides might act like estrogen. If you have any condition that might be made worse by exposure to estrogen, don't use American ginseng that contains ginsenosides. However, some American ginseng extracts have had the ginsenosides removed (Cold-FX, Afexa Life Sciences, Canada). American ginseng extracts such as these that contain no ginsenosides or contain only a low concentration of ginsenosides do not appear to act like estrogen.
Trouble sleeping (insomnia): High doses of American ginseng have been linked with insomnia. If you have trouble sleeping, use American ginseng with caution.
Schizophrenia (a mental disorder): High doses of American ginseng have been linked with sleep problems and agitation in people with schizophrenia . Be careful when using American ginseng if you have schizophrenia.
Surgery: American ginseng might affect blood sugar levels and might interfere with blood sugar control during and after surgery. Stop taking American ginseng at least 2 weeks before a scheduled surgery.
Warfarin (Coumadin)Interaction Rating: Major Do not take this combination.
Warfarin (Coumadin) is used to slow blood clotting. American ginseng has been reported to decrease the effectiveness of warfarin (Coumadin). Decreasing the effectiveness of warfarin (Coumadin) might increase the risk of clotting. It is unclear why this interaction might occur. To avoid this interaction, do not take American ginseng if you take warfarin (Coumadin).
Medications for depression (MAOIs)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.
American ginseng might stimulate the body. Some medications used for depression can also stimulate the body. Taking American ginseng along with these medications used for depression might cause side effects such as anxiousness, headache, restlessness, and insomnia.
Medications for diabetes (Antidiabetes drugs)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.
American ginseng might decrease blood sugar. Diabetes medications are also used to lower blood sugar. Taking American ginseng along with diabetes medications might cause your blood sugar to go too low. Monitor your blood sugar closely. The dose of your diabetes medication might need to be changed.
Some medications used for diabetes include glimepiride (Amaryl), glyburide (DiaBeta, Glynase PresTab, Micronase), insulin, pioglitazone (Actos), rosiglitazone (Avandia), chlorpropamide (Diabinese), glipizide (Glucotrol), tolbutamide (Orinase), and others.
Medications that decrease the immune system (Immunosuppressants)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.
American ginseng can increase the immune system. Taking American ginseng along with some medications that decrease the immune system might decrease the effectiveness of these medications.
Some medications that decrease the immune system include azathioprine (Imuran), basiliximab (Simulect), cyclosporine (Neoral, Sandimmune), daclizumab (Zenapax), muromonab-CD3 (OKT3, Orthoclone OKT3), mycophenolate (CellCept), tacrolimus (FK506, Prograf), sirolimus (Rapamune), prednisone (Deltasone, Orasone), and other corticosteroids (glucocorticoids).
The following doses have been studied in scientific research:
- For reducing blood sugar in people with type 2 diabetes: 3 grams up to 2 hours before a meal. American ginseng should be taken within 2 hours of a meal. If it is taken too long before eating, the blood sugar might become too low.100-200 mg of American ginseng have been taken daily for up to 8 weeks.
- For preventing upper respiratory tract infections such as the common cold or flu: a specific American ginseng extract called CVT-E002 (Cold-FX, Afexa Life Sciences, Canada) 200-400 mg twice daily for 3-6 months has been used.
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