CINV Flashcards
What are the risk factors for CINV?
(You Find Happy People Holding Love Always, YFHPHLA)
- Younger age (< 50 y/o)
- Females
- Hx of emesis during pregnancy
- Prone to motion sickness
- Hx of CINV
- Little or no previous alcohol intake (<1 glass/ day)
- Anxiety/ high pretreatment expectation of nausea
Name the 5HT3 antagonists.
What is their MOA?
Ondansetron, Granisetron, Palonosetron
Block serotonin receptors peripherally in the GI tract and centrally in the medulla
ADEs of 5HT3 antagonists?
- Headache
- Constipation (counsel on mgmt)
(may also increase LFTs and cause QTc prolongation)
What are the ADEs of dexamethasone?
- Incr in blood glucose levels
- Insomnia
- Anxiety
- Gastric upset
(less common: psychosis, reactivation of ulcers)
What is the MOA of NK1 receptor antagonists?
Binds to NK1 receptor and blocks substance P from binding. Attenuates vagal afferent signals and exerts antiemetic effects.
What are the ADEs of NK1 receptor antagonists?
- Fatigue
- Weakness
- Hiccups
- Nausea
What are the drug-drug interactions of NK1 receptor antagonists?
Steroids:
- May increase AUC of dexamethasone
Oral contraceptives:
- May reduce effectiveness. Recommend another form of birth control for women of childbearing age
Warfarin:
- May decrease INR. Check pt’s INR within 7-10 days of giving NK1 antagonists
BZDs:
- Increase concentration
What are the ADEs of Akynzeo tablet (Netupitant + Palonosetron)?
- Headache
- Weakness
- Dyspepsia
- Fatigue
- Constipation
- Erythema
MOA of metoclopramide (dopamine antagonist)?
Main:
- Blocks dopamine receptors in CTZ (central)
- Blocks 5HT3 receptors in gut (peripheral)
Others:
- Stimulates cholinergic activity in gut
- Increases gut motility
What are the ADEs of metoclopramide (dopamine antagonist)?
- Mild sedation
- Diarrhea
- EPSE (dystonia, akathisia), which can be mitigated by diphenhydramine/ benztropine
What drug MUST we AVOID with metoclopramide and why?
AVOID metoclopramide and olanzapine due to increased risk of EPSEs, neuroleptic malignant syndrome
What are adjunctive agents for refractory CINV?
What are their MOAs?
- Phenothiazines (prochlorperazine, chlorpromazine, promethazine)
- Butyrophenones (haloperidol)
MOA: block dopamine receptors in CTZ
Dosing of phenothiazines (prochlorperazine)?
PO 10mg TDS/ QDS PRN
Dosing of Butyrophenones (haloperidol)?
PO/IV 0.5-2mg Q4-6H
ADEs of phenothiazines (prochlorperazine, chlorpromazine, promethazine)?
- Drowsiness
- Hypotension
- Akathisia
- Dystonia
- EPSE
ADEs of Butyrophenones (haloperidol)?
- Sedation
- EPSE
What is the choice of drug for anticipatory CINV/ breakthrough CINV with anxiety component?
Benzodiazepines (Lorazepam)
What are the dosings of BZDs?
PO alprazolam 0.5-1mg
PO lorazepam 0.5-2mg
give the night BEFORE chemoTx and 1-2h BEFORE chemoTx
ADEs of Benzodiazepines (Lorazepam)?
- Drowsiness
- Dizziness
- Hypotension
- Anterograde amnesia (which helps with the anticipatory CINV)
- Urinary incontinence
- Paradoxical reactions (hyperactive, aggressive behaviour)
MOA of Olanzapine (atypical antipsychotic)?
Blocks multiple neurotransmitters including dopamine, serotonin, catecholamines, acetylcholine, histamine
ADEs of Olanzapine (atypical antipsychotic)?
Why do we need to use with caution in older adults?
- Sedation
- Dry mouth
- Increased appetite
- Weight gain
- Postural hypotension
- QTc prolongation
- Dizziness
- A/w elevated risk of hyperlipidemia, hyperglycemia, and new-onset diabetes. Caution in older adults due to incr risk of death and dementia-related psychosis
What are the general principles of breakthrough CINV?
- Give different classes of drug to target other MOAs
- If PO not feasible due to ongoing vomiting, try IV/ rectal route
- Hydration and fluid repletion for losses
What are some non-pharmacoTx for CINV?
- Small, frequent meals. Avoid heavy meals
- Avoid greasy, spicy, very sweet/ salty foods, foods with strong flavours/ smells
- Sucking on candy
- Sip small amounts of fluids instead of drinking one full glass
- Avoid caffeinated beverages
- Avoid lying flat 2h after eating
What are multi-day regimens?
Prophylactic Tx for expected emetogenicity on each day of chemoTx (most emetogenic risk drug) + cover delayed prophylaxis for 2-3 days after chemoTx completed
