Anti-emetic and Anti-nausea Drugs Flashcards
What suffix of drugs are serotonin (5-HT3) receptor antagonists?
-setron
Dolastron
Granisetron
Ondansetron
Palanosetron
How effective are serotonin (5-HT3) receptor antagonists?
What were they initially developed for?
What is the MOA?
Strong anti-emetic agents
Developed for chemo-induced N/V (CINV)
Block serotonin type-3 at vagal n. terminals and blocks transmission to CTZ. Also blocks serotonin release from intestinal enterochromaffin cells.
What are some therapeutic uses for serotonin (5-HT3) receptor antagonists? (4)
CINV
Radiation induced NV (RINV)
Post-op NV (PONV)
NV of pregnancy (NVP)
What are some adverse effects of serotonin (5-HT3) receptor antagonists? (3)
Which one is most worrisome?
CNS (HA)
GI (constipation/vomiting) - Serotonin syndrome
Dose-dependent QT prolongation (Torsades) - most worrisome
Which serotonin (5-HT3) receptor antagonists have long half-lives?
Palonostron
Sustained-release formulation of Granisetron (SQ)
What are 2 drug interactions in serotonin (5-HT3) receptor antagonists?
QT-prolonging agents
Anti-arrhythmics
What suffix of drugs are neurokinin (NK1) receptor antagonists?
-pitant
Which 2 neurokinin (NK1) receptor antagonists are used only in combo with Palonostron?
Netupitant
Fosnetupitant
What is the strength of neurokinin (NK1) receptor antagonists?
What is the MOA?
Moderate anti-emetic agents
Blocks neurokinin1 (supstance P) receptors in CTZ/VC
What are 2 therapeutic uses of neurokinin (NK1) receptor antagonists?
Chemo-induced NV (CINV) - most effective when used with glucocorticosteroid and 5-HT3 antagonist
Prophylaxis of post-op NV (PONV) - only Aprepitant
What suffices of drugs are histamine (H1) receptor antagonists?
- amine
- inate
- zine
What is Doxylamine given with?
Pyridoxine (B6)
What is the strength of histamine (H1) receptor antagonists?
What is the MOA?
What properties do some of these agents exhibit?
Weak anti-emetic drugs
Blockade of H1 receptor in VC and vestibular system.
Agents exhibit varying levels of central anticholinergic properties at level of CTZ.
What are some therapeutic uses of histamine (H1) receptor antagonists?
Mild NV
PONV
NVP (doxylamine/B6)
Motion sickness
Add on to CINV and RINV
What are the side effects of histamine (H1) receptor antagonists?
Classic anti-cholinergic effects: drowsiness, dry mouth, constipation, urine retention, blurred vision, etc.
What are drug interactions with histamine (H1) receptor antagonists?
Other agents that also induce anticholinergic effects
What are the 2 types of drugs that are dopamine (D2) receptor antagonists?
Phenothiazines: Chlorpromazine, Perphenazine, Prochlorperazine
Metoclopramide
What is the strength of dopamine (D2) receptor antagonists?
What is the MOA?
What unique MOA does Metoclopramide have?
Weak to moderate
Block D2 receptors in CTZ
Metclopramide can also stimule ACh actions in GI and enhance motility and increase LES tone.
What are some therapeutic uses for dopamine (D2) receptor antagonists?
Mild NV Gastroparesis/dysmotility (metoclopramide) PONV NVP CINV RINV
What are the adverse effects of dopamine (D2) receptor antagonists?
Classic anti-cholinergic effects: drowsiness, dry mouth, constipation, urine retention, blurred vision, etc.
What are the major drug interactions for dopamine receptor antagonists? (3)
Other agents that induce anticholinergic-related side effects
Anti-arrhythmics
Anti-hypertensives
What is the MOA of Scopolamine?
Muscarinic (M1) receptor antagonist
What is the strength muscarinic receptor blockers?
What’s it used for mostly?
How long is the patch worn for?
What kind of properties does it have?
Weak
Motion sickness
72 hrs.
Significant anti-cholinergic properties
What are the side effects of muscarinic receptor blockers?
What is a common drug interaction?
Classic anti-cholinergic effects
Only agents that also induce anti-cholinergic related side effects
What are the 2 cannabinoid receptor agonists?
Dronabinol
Nabilone
What is the strength of cannabinoid receptor agonists?
What are they reserved for?
What is the MOA?
Strong
Treatment-resistant CINV
Decreases excitability of neurons
What are some side effects of cannabinoid receptor agonists?
Euphoria/irritability Vertigo Sedation Dry mouth Impaired memory
What are some drug interactions of cannabinoid receptor agonists? (3)
CNS depressants
Cardiovascular agents
Sympathomimetics
Post-chemo
When does acute NV occur?
When does chronic NV occur?
When does anticipatory NV occur?
What should proper therapy focus on?
Acute - <24 hrs after chemo
Chronic - >24 hrs after chemo
Anticipatory - before chemo given
Focus on prevention!
What is the high-emetic regimen? (3-drug regimen)
What can be given if the pt. does not respond?
When is it given?
NK1 receptor antagonist
5-HT3 receptor antagonist
Corticosteroid (Dexamethasone)
Can give a 4th drug: D2 antagonist or cannabinoid
Prior to chemo and for 3 days
What is the moderate-emetogenic regimen? (2-drug regimen)
What can be given if the pt. does not respond?
When is it given?
5-HT3 receptor antagonist (Palanos/Granis SQ)
Corticosteroid (Dexamethasone)
May add NK1 (3 drug regimen), may add cannabinoid (4 drug)
Prior to chemo and for 2 days
What is the low-emetogenic regimen? (1-drug regimen)
When is it given?
One of: Corticosteroids, 5-HT3 receptor antagonist, Metoclopramide or Prochlorperazine
Given prior to chemo only
What are 3 drug options to treat motion sickness?
Scopolamine
Dimenhydrinate
Meclizine
What are 2 drug options to treat vertigo?
Meclizine
Cyclizine
What drug will treat diabetic gastroparesis (dysmotility)?
Metoclopramide
What type of therapy should be given in PINV?
Stepped-therapy
- Vit B6 or H1 antagonist (w/ Vit B6) or 5-HT3 antagonist
- D2 antagonist
- Steroid or a different D2 antagonist
