vomiting Flashcards
name the 2 physiological trigger for vomiting and how they work
5HT
Substance P
Trigger vagus nerve that has specific receptors and sends AP to brain VC
what type of drug are ‘setrons’
5HT3 receptor antagonists
how do 5HT3 receptor antagonists work
competitively block the peripheral and central receptors for 5HT3
what would setrons be used for
chemotherapy and radiation
example of 5HT3 antagonist (2)
ondansetron, palonosetron
how do muscarinic ACh receptor antagonists work?
directly inhibit GI movement by antagonising the ACh receptors that would normally be associated with parasympathetic system (i.e. stimulate GI movement)
name ACh receptor antagonists (2)
hyoscine, scopolamine
what are ACH receptor antagonists used for?
motion sickness, prophylaxis
how do histamine H1 receptor antagonists work?
competitively block H1 receptors in the VC and CNS (causing sedation)
why would you use H1 receptor antagonists
motion sickness, inner ear (vertigo), post operative nausea and vomiting
give 2 examples of H1 receptor antagonists
clyczizine, cinnarizine
why would you give dopamine receptor antagonists?
drug induces vomiting and GI disorders
what receptors do dopamine antagonists block? and where?
centrally block D2 and D3 receptors in the CTZ
give 2 examples of dopamine receptor antagonists
metoclopramide (causes parkinson like symptoms)
domperidone
when would you use NK1 receptor antagonists
chemotherapy and used with 5HT3 + dexamethasone (steroid)
