Ginger, the rhizome of Zingiber officinale, is one of the most widely used species of the ginger family (Zingiberaceae) and is a common condiment for various foods and beverages. Ginger has a long history of medicinal use dating back 2,500 years in China and India for conditions such as headaches, nausea, rheumatism, and colds.  Characterized in traditional Chinese medicine as spicy and hot, ginger is claimed to warm the body and treat cold extremities, improve a weak and tardy pulse, address a pale complexion, and strengthen the body after blood loss. 
Ginger contains a number of pungent constituents and active ingredients. Steam distillation of powdered ginger produces ginger oil, which contains a high proportion of sesquiterpene hydrocarbons, predominantly zingiberene.  The major pungent compounds in ginger, from studies of the lipophilic rhizome extracts, have yielded potentially active gingerols, which can be converted to shogaols, zingerone, and paradol.  The compound 6-gingerol appears to be responsible for its characteristic taste. Zingerone and shogaols are found in small amounts in fresh ginger and in larger amounts in dried or extracted products.
Mechanisms of Action
The mechanism underlying ginger’s anti-emetic activity is not clearly understood, but the aromatic, spasmolytic, carminative, and absorbent properties of ginger suggest it has direct effects on the gastrointestinal tract. 
Studies do not indicate ginger has influence within the vestibular or oculomotor system.  A mechanism involving the central nervous system cannot be ruled out, considering several of ginger’s components antagonize serotonin type-3 receptors; however, this has not been clearly demonstrated. [7–9] The compounds 6-gingerol and 6-shogaol have been shown to have a number of pharmacological activities, including antipyretic, analgesic, antitussive, and hypotensive effects.  Ginger extracts exhibit inhibition of platelet aggregation and thromboxane synthesis in vitro, [11–15] which has led to concerns ginger extracts may prolong bleeding; however, several European studies using ginger orally did not find any significant anticoagulant effects in vivo.  Daily consumption of 15 g raw ginger rhizome or 40 g cooked rhizome by 18 healthy volunteers for two weeks failed to decrease platelet cyclooxygenase activity.  Similarly, differences were not found in bleeding time, platelet count, and platelet functioning when eight healthy volunteers were given a single 2-gram dose of the dried rhizome or placebo.  In vitro studies suggest ginger may produce anti-inflammatory effects by inhibiting arachidonic acid metabolism in both the cyclooxygenase and lipoxygenase pathways. [19–21]