Q: Dear Dr. Mao,
Are there any hazards to taking ginseng? Which variety is the best to use?
A: There are actually three different herbs commonly called ginseng: Asian or Korean ginseng (Panax ginseng), American ginseng (Panax quinquefolius), and Siberian “ginseng” (Eleutherococcus senticosus). (The latter herb is actually not ginseng at all, but some herbalists believe that it functions identically.)
The various forms of ginseng appear to be nontoxic, both in the short and long term, according to the results of studies in mice, rats, chickens, and dwarf pigs. Ginseng also does not seem to be carcinogenic.
Side effects are rare. Occasionally women report menstrual abnormalities and/or breast tenderness when they take ginseng, and overstimulation and insomnia have also been reported. Unconfirmed reports suggest that highly excessive dosages of ginseng can raise blood pressure, increase heart rate, and possibly cause other significant effects.
Safety in young children, pregnant or nursing women, or those with severe liver or kidney disease has not been established.