NURS 2514 Week 2 Upper & Lower GI
Pharmacology Exam Study Guide
Ondansetron - ANSWER Type: antiemetic
Class: Serotonin Receptor Antagonists
MOA: Acts on serotonin blocking receptors = less available serotonin In CTZ
Adverse Effects: Headache, constipation, diarrhea, dizziness Urinary retention, muscle
pain QT PROLONGATION (Most Important)
Dexamethasone - ANSWER Type: antiemetic
Class: glucocorticoid
MOA: unknown
Adverse Effects: No negative effects when used for symptom management briefly
Nursing Considerations: used for nausea associated with chemotherapy. Can be used
alone or combined with other antiemetics (Ondansetron)
Metoclopramide - ANSWER Type: antiemetic
Class: Dopamine Antagonist
MOA: Blocks dopamine and serotonin receptors in the CTZ, enhances upper GI tract
response to acetycholine (↑ peristalsis)
Adverse Effects: in high doses, diarrhea and sedation are common
with long term use: risk of tardive dyskinesia (repetitive, involuntary movements of
arms, legs, facial muscles)
Counterindication: patients with GI obstruction, perforation or hemorrhage Due to
increased peristalsis
Nursing Considerations: GI Assessment, Assess mental status (drowsiness) Look for
uncontrolled movement
Nabilone - ANSWER Type: antiemetic
Class: cannabinoid
MOA: activation of receptors around the vomiting center
, Effect: used to suppress chemo induced nausea and vomiting
Adverse Effects: CNS: temporal disintegration, dissociation (avoid in patients with
psychiatric disorders)
CVS: tachycardia & hypotension (avoid in patients with cardiovascular disease)
Nursing Considerations: monitor for drowsiness
Dimenhydrinate - ANSWER Type: antiemetic
Class: antihistamine drugs (h1 receptor blockers)
MOA: Blocks H1 receptors in the GI tract and muscarinic receptors in the vestibular
system (anticholinergic)
Indications: Motion sickness, radiation sickness, post-op nausea, drug-induced nausea
Adverse Effects: drowsiness, dry mouth & constipation, avoid giving with other CNS
depressants, should not be taken with a hx of glaucoma or chronic lung disease,
difficulty urinating
Nursing Considerations: GI assessment, Assess alertness (safety), Vital signs (check
often with CVD), Monitor for signs of retention (bowel and bladder)
Scopolamine - ANSWER Type: antiemetic
Class: Muscarinic Antagonist
MOA: Blocks nerve impulses between vestibular apparatus in inner ear and vomiting
center
Effect: best drug for preventing and treating motion sickness
Adverse Effects: Dry mouth, blurred vision, drowsiness
Nursing Considerations: GI assessment, Monitor for signs of retention (bowel &
bladder), Assess alertness (safety)
Psyllium - ANSWER Type: laxative
Class: bulk forming
MOA: Similar action to fiber (↑bulk leads to soft formed stool)
Adverse Effect: Should be administered with large glass of water to avoid
obstruction/impaction (esophageal)
Lactulose - ANSWER Type: laxative
Pharmacology Exam Study Guide
Ondansetron - ANSWER Type: antiemetic
Class: Serotonin Receptor Antagonists
MOA: Acts on serotonin blocking receptors = less available serotonin In CTZ
Adverse Effects: Headache, constipation, diarrhea, dizziness Urinary retention, muscle
pain QT PROLONGATION (Most Important)
Dexamethasone - ANSWER Type: antiemetic
Class: glucocorticoid
MOA: unknown
Adverse Effects: No negative effects when used for symptom management briefly
Nursing Considerations: used for nausea associated with chemotherapy. Can be used
alone or combined with other antiemetics (Ondansetron)
Metoclopramide - ANSWER Type: antiemetic
Class: Dopamine Antagonist
MOA: Blocks dopamine and serotonin receptors in the CTZ, enhances upper GI tract
response to acetycholine (↑ peristalsis)
Adverse Effects: in high doses, diarrhea and sedation are common
with long term use: risk of tardive dyskinesia (repetitive, involuntary movements of
arms, legs, facial muscles)
Counterindication: patients with GI obstruction, perforation or hemorrhage Due to
increased peristalsis
Nursing Considerations: GI Assessment, Assess mental status (drowsiness) Look for
uncontrolled movement
Nabilone - ANSWER Type: antiemetic
Class: cannabinoid
MOA: activation of receptors around the vomiting center
, Effect: used to suppress chemo induced nausea and vomiting
Adverse Effects: CNS: temporal disintegration, dissociation (avoid in patients with
psychiatric disorders)
CVS: tachycardia & hypotension (avoid in patients with cardiovascular disease)
Nursing Considerations: monitor for drowsiness
Dimenhydrinate - ANSWER Type: antiemetic
Class: antihistamine drugs (h1 receptor blockers)
MOA: Blocks H1 receptors in the GI tract and muscarinic receptors in the vestibular
system (anticholinergic)
Indications: Motion sickness, radiation sickness, post-op nausea, drug-induced nausea
Adverse Effects: drowsiness, dry mouth & constipation, avoid giving with other CNS
depressants, should not be taken with a hx of glaucoma or chronic lung disease,
difficulty urinating
Nursing Considerations: GI assessment, Assess alertness (safety), Vital signs (check
often with CVD), Monitor for signs of retention (bowel and bladder)
Scopolamine - ANSWER Type: antiemetic
Class: Muscarinic Antagonist
MOA: Blocks nerve impulses between vestibular apparatus in inner ear and vomiting
center
Effect: best drug for preventing and treating motion sickness
Adverse Effects: Dry mouth, blurred vision, drowsiness
Nursing Considerations: GI assessment, Monitor for signs of retention (bowel &
bladder), Assess alertness (safety)
Psyllium - ANSWER Type: laxative
Class: bulk forming
MOA: Similar action to fiber (↑bulk leads to soft formed stool)
Adverse Effect: Should be administered with large glass of water to avoid
obstruction/impaction (esophageal)
Lactulose - ANSWER Type: laxative
