Antiemetics Flashcards
name the antiemetics (8)
- bismuth subsalicylate (salicylate)
- diphenhydramine (antihistamine)
- promethazine (antihistamine, anticholinergic, dopamine antagonist)
- scopolamine (anticholinergic)
- ondansetron (serotonin antagonist)
- Benzodiazepines (-pam/-lam)
- dexamethasone (Glucocorticoid)
- dronabinol (Cannabinoid)
- methylprednisolone (Glucocorticoid)
bismuth subsalicylate route (1.5)
PO - liquid or chewable tablet
bismuth subsalicylate MOA (3)
- adsorbs bacteria/toxins that are causing nausea
- diarrhea/indigestion
- decreases absorption of other drugs
bismuth subsalicylate nursing (3)
- avoid taking other drugs
- avoid if under 19 years old = will cause Reye’s syndrome
- avoid if allergic reaction to ASA or NSAIDs (aspirin has the salicylate in it just like this drug)
bismuth subsalicylate side effects (6)
- slurred speech
- hearing loss
- vision problems
- AMS
- muscle spasm
- harmless and temporary black discoloration of stools/tongue
bismuth subsalicylate contraindications (1)
pregnancy (teratogenic: fetal malformation)
causes of the vomiting center stimulated by visceral and the NTs
visceral: nose, mouth, stomach, intestine stimulation
- odor, smell, taste
- food intolerance
- pregnancy
- infection
- pain
NTs:
- dopamine
- serotonin
causes of the vomiting center stimulated by CTZ and the NTs
- drugs
- toxins like opioids, chemo, anesthesia
NTs:
- dopamine
- serotonin
causes of the vomiting center stimulated by vestibular nerve and CNS and the NTs
- inner ear disease
- motion sickness
- ear infection/inflammation
NTs:
- histamine
- Ach
vomiting will result in / nursing
- loss of fluid/electrolytes => monitor I/O & replace - metabolic alkalosis => monitor ABG and correct - aspiration => treat nausea & prevent vomiting - esophageal ulcer => treat nausea & prevent vomiting
non-pharm measures to treat vomiting
- flat ginger ale
- weak tea
- gelatin, crackers/saltines, toast
- acupressure
- Pedialyte (for children) or Gatorade (for adults) or IVF (for all)
- vitamin B6 (motion sickness and morning sickness)
- NG tube and intermittent suctioning (decompression)
bismuth subsalicylate OTC or Rx?
OTC, this is the brand name pepto-bismal
diphenhydramine routes (3)
- PO
- IM
- IV
diphenhydramine and promethazine MOA (1)
inhibit vestibular stimulation in the inner ear
diphenhydramine indication (2)
- nausea
2. motion-sickness
diphenhydramine side effects (2)
- crossing the BBB: drowsiness, dizziness, fatigue, disturbed coordination, FALL
- –> 2nd use: insomnia, motion sickness - anticholinergic effects (SCARY BEAR)
promethazine routes (2)
- PO
- IV BUT it is a vesicant so only in an intact central line
promethazine and scopolamine indication (4)
- nausea
- motion-sickness
- Meniere’s Disease
- allergies
me, mine, Meniere’s Disease
diphenhydramine and promethazine nursing (2 w/ things to monitor)
- Anticholinergic effects
- Monitor VS (see code phrases)
- Monitor I/Os (urinary retention)
- Avoid with BPH, urinary retention, glaucoma, HTN, tachycardia
-
CNS depression
- Assess breath sounds (CNS depression => respiratory depression)
- avoid driving or operating dangerous machinery (FALL)
- Avoid other CNS depressants (ETOH, codeine)
- Hangover effect (residual drowsiness effect)
diphenhydramine and promethazine contraindications
- pregnancy
- lactation
- newborns
- children
scopolamine routes (4)
- transdermal patch
- PO
- IM
- IV
scopolamine and promethazine MOA (1)
inhibit vestibular stimulation in the inner ear
scopolamine and promethazine side effects
- CNS depressant: drowsiness!
- memory impairment:
- caution w/ older adults
- chronic resp diseases
promethazine (dopamine antagonist) MOA (1)
block dopaminergic receptors in the intestine and CTZ
promethazine (dopamine antagonist) as an antipsychotic vs antiemetic?
antipsychotic in large doses but an antiemetic in small doses
promethazine (dopamine antagonist) adverse side effects
CNS:
- seizure
- EPS (extrapyramidal syndrome)
promethazine (dopamine antagonist) contraindications (3)
- alcohol
- other CNS depressants
- other CNS stimulants
s/s of EPS
movement disorders SE
- dystonia
- akathisia
- Parkinsonism (resting tremors, bradykinesia to freezing, poor posture, rigidity)
- tardive dyskinesia
stop the med and give centrally acting anticholinergic like benztropine or diphenhydramine; Pt never goes back to normal
ondansetron routes (3)
- IV
- IM
- ODT (oral disintegrating tablet)**
ondansetron MOA
blocks serotonin in CTZ center in the brain and visceral stimulation
ondansetron side effects
- overall well tolerated, no EPS
- headache
- diarrhea
- dizziness
- fatigue
ondansetron adverse effect (1) and nursing
dysrhythmias
- monitor cardiac rhythm
- avoid in Hx of dysrhythmia
lorazepam and midazolam routes (3)
- PO
- IM
- IV
lorazepam and midazolam MOA (2)
- CNS depressant
- sedative (anxiolytic), hypnotic, amnestic
lorazepam and midazolam indications (2)
- most effective for chemo related nausea
2. often part of anesthesia induction
lorazepam and midazolam side effects
- lethargy
- poor balance
- resp suppression
- FALL
methylprednisolone route (1)
IV
dexamethasone route (1)
PO
methylprednisolone and dexamethasone indication
nausea associated with chemo “premedicated”
methylprednisolone and dexamethasone (glucocorticoid) side effects
- hyperglycemia (DM patients)
- leukocytosis (high WBCs) yet immunosuppressant!!!
- immunosuppressant: b/c its anti-inflammatory
- water/sodium retention:
- –>worsening of HF, edema, HTN = hypokalemia
- –>increased IOP (worsening glaucoma) - subQ tissue loss w/ chronic use = “paper skin” or “steroid skin”
- adrenal suppression = taper dose, b/c abrupt stop = adrenal crisis!!!!
- osteoporosis - take vit D, Ca and exercise
dronabinol route (1)
PO
dronabinol MOA
- unknown, affecting cerebral cortex
- schedule III
dronabinol indication
- N/V secondary to chemo
- appetite stimulant for AIDS, failure to thrive
dronabinol contraindicated
with psychiatric disorders
dronabinol side effects
- Mood changes
- euphoria**
- drowsiness
- dizziness
- HA
- depersonalization
- nightmares
- confusion
- incoordination
- memory lapse
- dry mouth
- orthostatic hypotension
- tachycardia
- FALL**
nursing for antiemetics
- If able to tolerate PO intake, encourage clear liquid intake (sports drinks)
- if not not able to tolerate PO intake, call to replace IV fluid and IV electrolytes
- Non-pharm always before AND along with pharmacotherapy
- Avoid polypharmacy with OTC & Rx.
- Avoid ETOH with antiemetics (risk of over-sedation)
- Fall precautions, driving (drowsiness, hangover effect)
- Avoid antiemetics during pregnancy (consult provider)
