GI protectants / Antiemetics Flashcards
Ondansetron dose
4 mg
Ondansetron onset
~ 30 minutes
Ondansetron peak
2 hours
Ondansetron duration
4 - 24 hours
Ondansetron MOA
5-HT3 receptor antagonist or serotonin antagonist
Ondansetron metabolism
hepatic metabolism
renal elimination
When is ondansetron contraindicated?
with decreased GI motility or decreased lower esophageal sphincter tone
Droperidol dose
0.625 - 2.5 mg
Droperidol onset
1 - 2 minutes
Droperidol peak
30 minutes
Droperidol duration
2 - 4 hours
Droperidol MOA
dopamine-2 (D2) receptor antagonist
Well known cardiac effect of droperidol
can prolong QT interval
Droperidol metabolism
hepatic metabolism
renal elimination
Diphenhydramine dose
50 mg
Diphenhydramine duration
3 - 6 hours
Diphenhydramine MOA
H1 antagonist
selectively antagonizes H1 receptors, blocking histamine activation of gastric parietal cell proton pump
Ranitidine dose
2 - 4 mg/kg
Ranitidine peak
1 - 3 hours
Ranitidine duration
1.5 - 2.5 hours
Ranitidine MOA
H2 antagonist
selectively antagonizes H2 receptors, blocking histamine activation of gastric parietal cell proton pump
Should the ranitidine dose be increased or decreased with advancing age and/or renal dysfunction?
decrease the dose
Ranitidine metabolism
hepatic metabolism
renal elimination
Diphenhydramine metabolism
hepatic metabolism
renal elimination
Omeprazole dose
20 mg PO
Omeprazole onset
2 - 4 hours
Omeprazole peak
2 - 4 hours
Omeprazole duration
> 24 hours
Omeprazole MOA
proton pump inhibitor
directly inhibits the H+/K+ ATP-ase proton pump, leading to an increase in gastric pH and a decrease in fluid volume
Omeprazole metabolism
hepatic metabolism
renal elimination
Metoclopramide dose
10 - 20 mg
Metoclopramide onset
1 - 2 minutes
Metoclopramide peak
5 minutes
Metoclopramide duration
1 - 2 hours
Metoclopramide MOA
GI prokinetic and dopamine-2 (D2) receptor antagonist
[produces selective cholinergic stimulation of GI tract by:
1) increasing SM tone in lower esophageal sphincter and stomach
2) increasing gastric and small intestine motility
3) relaxes pylorus and duodenum when stomach contracts]
Metoclopramide metabolism
hepatic metabolism
renal elimination