Goldenseal was used by Native Americans both as a yellow dye and for its curative properties. It has antimicrobial properties and is said to strengthen the functioning of the liver. It is dangerous when ingested in large quantities however. Goldenseal is also very expensive--it's popularity over the last few years has lead to overharvesting of the wild herb, and many herbalists now consider the plant off-limits to provide for its replenishment.

Goldenseal is often combined with echinacea in herbal medicines to give a one-two punch in curing various illnesses. It's an extremely powerful substance, and can cause a disruption in intestinal flora if taken too much. You really only want to take it if you're really sick, and only for short periods.