Chapter 4 BNF (Nausea and Labyrinth Disorders) Flashcards
What are the causes of N and V?
Drugs Labyrinthitis (inner ear infection) Motion Gut irritation Higher stimuli
How dose nausea occur?
vomiting centre triggered by chemoreceptor trigger zone?
antiemetics antagonise the CTZ
What dopamine antagonists are used in N and V?
Metoclopramide
Domperidone (parkinson’s)
Prochloperazine (migraine)
haloperidol, levopromazine (palliative )
which antihistamines are used in n and v?
Cinnarizine
cyclizine
promethazine (vertigo)
what antimuscarinc is used in n and v?
hyoscine hydrobromide (most effective in motion)
what 5ht3 antagonists are used in n and v?
ondansetron
granisetron
palonsetron
chemo, post op,
what other drugs are used in n and v?
dexamethasone
nabilone
aprepitant
When drug treatment is necessary, what medication can be used in N and V in pregnancy?
promethazine short term
prochloperazine
metoclopramide
What antiemetics can be used in prevention of post op N and V?
5HT3 Antagonists
Dexamethasone
Phenothiazines
cyclizine
How does Metoclopramide work?
D2 receptors on the CTZ
acts in the gut to promote emptying, prokinetic
what are the risks with Metoclopramide?
EPSEs (MHRA)
Max use 5 days, 18+, 10mg TDS
What are the side effects with Metoclopramide?
Acute dystonic reactions especially in young girls and elderly
Whats the difference between Metoclopramide and Domperidone?
Domperidone doesnt cross the BBB, no dystonia
Whats the risk with Domperidone?
serious cardiac reactions (MHRA) QT prolongation
max use 1 week 10mg TDS
What are the hallmarks of 5HT3 antagonists interactions?
QT prolongation serotonin syndrome hypokalemia drugs (causes torsades)
