Nausea pathways

Nausea pathways represent a complex physiological network responsible for the sensation of nausea and the reflex of vomiting. These pathways integrate signals from the gastrointestinal tract via the vagus nerve, the vestibular system, and the chemoreceptor trigger zone (CTZ) located in the area postrema of the medulla (NCBI, Neurobiology of Nausea and Vomiting, 2014). Key molecular mediators include serotonin acting on 5-HT3 receptors, substance P acting on NK1 receptors, dopamine acting on D2 receptors, histamine acting on H1 receptors, and acetylcholine acting on M1 receptors (StatPearls, Antiemetic Medications, 2023). Activation of these receptors leads to the stimulation of the central vomiting center, which coordinates the muscular actions of emesis. Pharmacological intervention typically involves blocking one or more of these receptor types to prevent or treat conditions like chemotherapy-induced nausea and vomiting (CINV), postoperative nausea and vomiting (PONV), or motion sickness (Mayo Clinic, Nausea and Vomiting, 2023). Because this term describes a collection of biological processes and multiple distinct molecular targets rather than a single protein, it is classified as a pathway rather than a specific therapeutic target.

Other names

Emetic reflexVomiting pathwaysChemoreceptor trigger zone signalingNausea and vomiting of pregnancy pathwaysCentral and peripheral emetic circuits

Antagonism of specific receptors within the pathway, including 5-HT3, NK1, D2, H1, and M1 receptors, to inhibit the transmission of emetic signals to the vomiting center in the medulla (StatPearls, Physiology, Vomiting, 2023).