Antiemetics Flashcards
What class of drug is Metoclopramide?
Dopamine 2 receptor antagonist
What are the common indications for Metoclopramide?
Post operative nausea, vomiting and certain digestive disorders.
What is the mechanism of action of Metoclopramide?
Central dopamine antagonist
Blocks messages from the CTZ (chemoreceptor trigger zone) and the vomiting centre
Peripheral cholinergic agonist. Increases tone and motility of the stomach and intestines, speeding up digestion- why it is good for GORD
What are the adverse effects of Metoclopramide?
Depression, diarrhoea, drowsiness, hypotension and galactorrhoea
What are the drug-drug interactions of Metoclopramide?
Anti-psychotic drugs, dopamine agonists
How can you remember Metoclopramide?
What class of drug is Ondansetron?
Serotonin antagonist
What are the common indications of Ondansetron?
To prevent nausea and vomiting in chemotherapy
What is the mechanism of action of Ondansetron?
Blocks afferent signals from the gut to the CTZ
Peripherally reduces GI motility and reduces GI secretions
What are the adverse effects of Ondansetron?
Constipation, headache, elevated liver enzymes
Extra-pyramidal effects- dystonia, parkinsonism
What are the warnings with Ondansetron?
Subacute abdominal obstruction, susceptible to long QT
What are the drug-drug interactions of Ondansetron?
Serotonin agonists, drugs that prolong the QT interval (Tramadol)
How can you remember Ondansetron?
