This site is intended for healthcare professionals

Go to /sign-in page

You can view 5 more pages before signing in

Physiology of vomiting

Last reviewed dd mmm yyyy. Last edited dd mmm yyyy

Authoring team

Vomiting is controlled by the emetic centre which is situated in the floor of the fourth ventricle. The emetic centre represents the final common pathway for stimuli from several sites included the chemoreceptor trigger zone - CTZ - located on the surface of the fourth ventricle, the meninges, cerebral cortex, vestibular apparatus and the gastrointestinal tract via vagus and sympathetic afferents. In the emetic centre and the CTZ there are high concentrations of dopamine receptors with associated cholinergic and H1 receptors.

Metoclopramide, phenothiazines, butyrophenones, and domperidone act mainly by antagonism at the dopamine receptors to reduce vomiting stimuli. Domperidone crosses the blood-brain barrier poorly and has mainly a peripheral action. Metoclopramide also has a peripheral action and increases gastro-oesophageal tone and increases stomach emptying due to a cholinergic effect. Serotonin antagonists such as Ondansetron probably have peripheral effects in the gut and a central action.

Related pages

Create an account to add page annotations

Add information to this page that would be handy to have on hand during a consultation, such as a web address or phone number. This information will always be displayed when you visit this page

The content herein is provided for informational purposes and does not replace the need to apply professional clinical judgement when diagnosing or treating any medical condition. A licensed medical practitioner should be consulted for diagnosis and treatment of any and all medical conditions.


Copyright 2024 Oxbridge Solutions Limited, a subsidiary of OmniaMed Communications Limited. All rights reserved. Any distribution or duplication of the information contained herein is strictly prohibited. Oxbridge Solutions receives funding from advertising but maintains editorial independence.