Domperidone is given in order to relieve nausea and vomiting; to increase the transit of food through the stomach (as a pro kinetic agent through increase in gastrointestinal peristalsis).
Domperidone is used to increase lactation (breast milk production) by release of pro lactin.
It is also used in the scientific study of the way dopamine (an important neurotransmitter) acts in the body.
Domperidone is a peripheral dopamine (D2) and (D3) receptor antagonist to provide relief from nausea by blocking receptors at the chemo-receptor trigger zone at the floor of the fourth ventricle.
It increases motility in the upper gastrointestinal tract to a moderate degree and increases[2] lower esophageal sphincter pressure by blocking dopamine receptors in the gastric antrum and the duodenum. It blocks dopamine receptors in the posterior pituitary gland increasing release of pro lactin which in turn increases lactation.