Wild ginger is not related to common ginger but is in the birthwort family, Aristolochiaceae. Several species grow commonly throughout Asia, Europe, and North America, and there seems to be little difference in therapeutic effects between them. The plant has a warm, spicy flavor, reminiscent of ginger, but is a little more bitter and acrid. The leaves are a strong emetic, and the whole plant contains aristolochic acid, a known mutagen and kidney toxin. However, several Chinese species have been used for over 2,000 years with little concern, as long as the traditional uses and dose are followed. If in doubt about using this herb, consult a qualified Chinese or western herbalist. Wild ginger is used in teas and tinctures in small amounts (1-3 grams/day) for up to 10 days to warm the "defensive vitality" or immune force in the outer layers of the body to dispel viral infections and increase blood circulation. The herb is indicated in colds and flu where a person has body aches and pain, chills, and low fever, but no sweating Ý especially after exposure to cold wind and dampness. It can also help resolve nasal mucus discharge in colds and flu, especially when it is free flowing and clear (not yellow or green and thick, which indicates pathogenic heat).