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SUCCESS STARTS HERE! LEARN, PRACTICE & EXCEL!
how does vomiting happen? Answer: 1.) chemoreceptor trigger zone (activated by
stomach/small intestine/blood) activates vomiting center
2.) sensory input directly activates vomiting center
what are some of the receptors in the chemo-receptor zone? Answer: 5-HT3 Serotonin receptor
DA2 dopamine receptor
what is the broad rule for treating emesis or diarrhea Answer: choice of drug (if any) should be
based off the root cause
most effective anti-emetic drugs Answer: serotonin 5-HT3 receptor antagonists: ondansetron
(zonfran)
Ondansetron (Zonfran) and other "-setron" Answer: Serotonin H-HT3 receptor antagonist
blocks receptor in the CTZ
Ondansetron (Zonfran) indications Answer: post-op
prevention of N/V
chemo/radiation
Ondansetron (Zonfran) route Answer: oral or IV push
ADRs of ondansetron (zonfran) Answer: could prolong QT interval!
(contraindicated with cardiac dysrhythmias, HF, electrolyte (especially potassium) imbalances
drowsiness
headache/dizziness
Dopamine antagonists Answer: anti-emetic, block dopamine receptors in the CTZ
phenothiazines, butyrophenones, metoclopramide
ADRs of dopamine antagonists Answer: anticholinergic side effects
hypotension
sedation
Extrapyramidal Symptoms (EPS) (Parkinson's like symptoms)
APPHIA – Crafted with Care and Precision for Academic Excellence.
1
, stop for uncontrolled facial movements!
Promethazine and important considerations Answer: phenothiazine and dopamine receptor
antagonist
can lead to resp. depression especially in kids
contraindicated in children less than 2 years!!
vesicant
Prochlorperazine Answer: phenothiazine and dopamine receptor antagonist
Droperidol (Inapsine) and important considerations Answer: Butyrophenone and dopamine
antagonist
ADRs= prolonged QT interval (black box warning)!!
Haloperidol (Haldol) Answer: Butyrophenone and dopamine antagonist
Metoclopramide (Reglan) Answer: dopamine antagonist
also pro-kinetic
Metoclopramide (Reglan) indications Answer: pre-op: clears GI system and prevents N/V
Metoclopramide (Reglan) contraindications Answer: contraindicated with GI issues (bleed,
obstruction)
Cannabinoids Answer: anti-emetics, activate cannabinoid receptors near N/V receptor
Dronabinol (Marinol)
Nabilone (Cesamet)
Cannabinoids indications Answer: chemotherapy induced N/V
Dronabinol (Marinol) Answer: Cannabinoid
also used to stimulate appetite in pts with AIDS
Nabilone (Cesamet) Answer: Cannabinoid
ADRs of Cannabinoids Answer: abuse potential
similar subjective effects as smoking
tachycardia, hypotension
drowsiness
Cannabinoids contraindications Answer: shouldn't be taken with alcohol
APPHIA – Crafted with Care and Precision for Academic Excellence.
2
SUCCESS STARTS HERE! LEARN, PRACTICE & EXCEL!
how does vomiting happen? Answer: 1.) chemoreceptor trigger zone (activated by
stomach/small intestine/blood) activates vomiting center
2.) sensory input directly activates vomiting center
what are some of the receptors in the chemo-receptor zone? Answer: 5-HT3 Serotonin receptor
DA2 dopamine receptor
what is the broad rule for treating emesis or diarrhea Answer: choice of drug (if any) should be
based off the root cause
most effective anti-emetic drugs Answer: serotonin 5-HT3 receptor antagonists: ondansetron
(zonfran)
Ondansetron (Zonfran) and other "-setron" Answer: Serotonin H-HT3 receptor antagonist
blocks receptor in the CTZ
Ondansetron (Zonfran) indications Answer: post-op
prevention of N/V
chemo/radiation
Ondansetron (Zonfran) route Answer: oral or IV push
ADRs of ondansetron (zonfran) Answer: could prolong QT interval!
(contraindicated with cardiac dysrhythmias, HF, electrolyte (especially potassium) imbalances
drowsiness
headache/dizziness
Dopamine antagonists Answer: anti-emetic, block dopamine receptors in the CTZ
phenothiazines, butyrophenones, metoclopramide
ADRs of dopamine antagonists Answer: anticholinergic side effects
hypotension
sedation
Extrapyramidal Symptoms (EPS) (Parkinson's like symptoms)
APPHIA – Crafted with Care and Precision for Academic Excellence.
1
, stop for uncontrolled facial movements!
Promethazine and important considerations Answer: phenothiazine and dopamine receptor
antagonist
can lead to resp. depression especially in kids
contraindicated in children less than 2 years!!
vesicant
Prochlorperazine Answer: phenothiazine and dopamine receptor antagonist
Droperidol (Inapsine) and important considerations Answer: Butyrophenone and dopamine
antagonist
ADRs= prolonged QT interval (black box warning)!!
Haloperidol (Haldol) Answer: Butyrophenone and dopamine antagonist
Metoclopramide (Reglan) Answer: dopamine antagonist
also pro-kinetic
Metoclopramide (Reglan) indications Answer: pre-op: clears GI system and prevents N/V
Metoclopramide (Reglan) contraindications Answer: contraindicated with GI issues (bleed,
obstruction)
Cannabinoids Answer: anti-emetics, activate cannabinoid receptors near N/V receptor
Dronabinol (Marinol)
Nabilone (Cesamet)
Cannabinoids indications Answer: chemotherapy induced N/V
Dronabinol (Marinol) Answer: Cannabinoid
also used to stimulate appetite in pts with AIDS
Nabilone (Cesamet) Answer: Cannabinoid
ADRs of Cannabinoids Answer: abuse potential
similar subjective effects as smoking
tachycardia, hypotension
drowsiness
Cannabinoids contraindications Answer: shouldn't be taken with alcohol
APPHIA – Crafted with Care and Precision for Academic Excellence.
2
