A drug used to prevent nausea or vomiting. An antiemetic may act by a wide range of mechanisms: it might affect the medullary control centres (the vomiting centre and the chemoreceptive trigger zone) or affect the peripheral receptors.
Metoclopramide is a dopamine D2 antagonist. It is used (particularly as the monohydrochloride monohydrate, commonly known as metoclopramide hydrochloride, but also as the dihydrochloride monohydrate) to increase motility of the upper gastrointestinal tract in disorders such as gastro-oesophageal reflux, and for the treatment of nausea and vomiting associated with various gastrointestinal disorders, with migraine, following surgery, and with cancer therapy. Although chemically related to procainamide, metoclopramide does not possess local anaesthetic or anti-arrhythmic properties.