there are two main vomiting centres which are both located within the medulla
including…
the vomiting (emetic) centre
-Responds to both vagal and sympthateic efferents
Chemoreceptor trigger zone (CTZ)
CTZ is in the area postrema in the floor of the 4th ventricle
The CTZ is especially sensitive to chemical stimuli and it is the main site of action of drugs which stimulate vomiting. and can also be the site for drugs aimed to act as it has a part of it which has a permuable BBB
as shown in the diagram below the vomiting centre is the main centre for processing all information from other sources and initiating an emesis response.