Ginseng acts as a stimulant for some people, causing nervousness and insomnia. Long-term use or high doses may cause stomach upset, headaches, dizziness or other symptoms. Breast tenderness and menstrual changes may occur in women who use ginseng for a long period. There have also been some reports of allergic reactions to ginseng.
A doctor should be consulted before ginseng is taken with other medications. For example, ginseng can impact blood sugar levels, and therefore it could impact the drugs taken by diabetics. It also may interact with warfarin and with some medicines for depression
To avoid the potential side effects, some experts suggest that ginseng shouldn't be used for more than three months, or sometimes just a few weeks, at a time. A doctor may recommend taking periodic breaks of a week or more from using ginseng. Since the stimulant effect of ginseng may be amplified by caffeine, coffee and similar beverages should be avoided. Ginseng is not recommended for children or for women who are pregnant or breastfeeding.
Ginseng is one of the most popular herbal medicines in the world. The potential benefits include improvements to the immune system, lower blood sugar and improved concentration. However, standard doses of ginseng have not been established for any condition.
American ginseng is possibly effective in the treatment of diabetes and respiratory infections, but there is insufficient evidence to rate it for other medical conditions, according to MedlinePlus. Asian ginseng is possibly effective for treating Alzheimer's disease, chronic obstructive pulmonary disease, high blood pressure and sexual conditions, including erectile dysfunction.
Asian or Panax ginseng should not be confused with American ginseng, WebMD says. The site lists different uses for the two types of ginseng, some of which overlap, especially in the area of anti-inflammation and boosting the immune system. Asian ginseng is considered more stimulating, while American ginseng is used as an aid to relaxation.
Conclusive evidence of the efficacy of the two main types of ginseng in fighting cancer, heart disease, high blood pressure, erectile dysfunction and hepatitis C has not been found, but researchers have found some promise in the root, according to WebMD. Some studies show ginseng helps modestly with learning and concentration. While some studies of ginseng's use in lowering blood sugar, boosting the immune system and fighting disease show some positive results, its benefits in most medical uses are inconclusive.