Ginger is a perennial plant native to southern Asia. The part of the plant that is used for medicinal purposes is the rhizome – or underground stem. Chinese medical texts from the fourth century BC indicate that ginger was already being used for nausea, diarrhea, stomach aches, cholera, toothaches, bleeding, and rheumatism. Ginger was later used by Chinese herbalists to boost immunity. Today, ginger is often used for motion sickness, and nausea.