pharmacology

Question 1

Mechanism of action of ondansetron?

Answer 1

5-HT3 antagonist - blocks serotonin receptors
Acts centrally and on the gut (to constipate!)

most useful in chemotherapy induced nausea + pruritus secondary to renal failure

Question 2

Mechanism of action of domeperidone?

Answer 2

dopamine antagonist

gut ONLY - poor blood brain barrer penetration

Question 3

Mechanism of haloperidol?

Answer 3

dopamine antagonist - in the CTZ

Question 4

mechanism of cyclizine?

Answer 4

histamine receptors in the vomiting centre

Question 5

mechanism of action of metoclopramide?

Answer 5

dopamine antagonism in CTZ

5HT3 in gut

Question 6

mechanism of action of levomepromazine?

Answer 6

5Ht2, dopamine, acteylcholine, histamine receptors - central, broad spectrum

Question 7

mechanism of hyoscine hydrobromide?

Answer 7

ach recptor antagonist

Question 8

which antiemetics cause extrapyramidal side effects?

Answer 8

haloperidol
levomepromazine
metoclopramide
domeperidone

Question 9

what are the extrapyramidal side effects?

Answer 9

restless
tardive dyskinesia
akathesia

Question 10

which antiemetics can cause anticholinergic side effects?

Answer 10

levomepromazine

cyclizine

Question 11

what are anticholinergic side effects?

Answer 11

dry mouth
dry eyes
constipation
urinary retention
agitation + restlessness