Chapter 52 - Antiemetic and Antinausea Drugs Flashcards
What is nausea?
Unpleasant feeling preceding vomiting
What is Emesis?
Vomiting.
Forcible emptying of gastric/intestinal contents
What drugs are used to relieve nausea/vomiting?
Antiemetic drugs
6 pharmacologic managemetn of nausea/vomiting?
- Dopamine antagonists
- Antihistamines
- Anticholinergics
- Prokinetic agents
- Serotonin blockers
- Tetrahydrocannabinoids (THC)
Causes of nausea/vomiting? (11, and they literally all start with M)
Metastases Meningeal irritation Movement Mental anxiety Medications Mucosal irritation Mechanical obstruction Motility Metabolic Microbes Myocardial
What is the MOA of anticholinergic drugs?
MOA = Mechanism of Action
- bind to and block ACh receptors in inner ear labyrinth
- block transmission of nauseating stimuli to CTZ
- also block transmission of nauseating stimula from reticular formation to the VC
Indications of anticholinergic drugs?
motion sickness, pre-surgical secretion reduction, N/V
What is scopolamine and what is it used for?
Anticholinergic drug in transdermal patch form used for motion sickness
What is the MOA of antihistamine drugs (H1 receptor blockers)?
- inhibit ACh by binding to H1 receptors
2. prevent cholinergic stimulation in vestibular/reticular areas, preventing N/V
Indications of antihistamine drugs?
motion sickness, nonproductive cough, allergy symptoms, sedation, N/V
3 Antihistamine drugs
ADDM
- dimenhydrinate (Dramamine(
- diphenhydramine (Benadryl)
- meclizine (Antivert)
Antihistamines Don’t Deliver Madness
MOA of antidopaminergic drugs
block dopamine receptors on the CTZ
Indications of antidopaminergic drugs?
used for psychotic disorders, intractable hiccups (i find this funny), N/V
3 antidopaminergic drugs, and which is controversial/why?
- prochlorperazine (Compazine)
- promethazine (Phenergan)
- droperidol (Inapsine): controversial use b/c associated cardiac dysrhythmia
MOA of prokinetic drugs
- block dopamine in the CTZ
- cause CTZ to be desensitized to ipulses it receives from the GI tract
- stimulates peristalsis in GI tract, enhancing emptying of stomach contents
Indications of prokinetic drugs
GERD, delayed gastric emptying, N/V
Example of a prokinetic drug
metoclopramide (Reglan)
long term use may cause irreversible tardive dyskinesia
MOA of serotonin blockers
block serotonin receptors in the GI tract, CTZ, and VC
Indication of serotonin blockers
N/V in pt’s receiving chemotherapy and for postoperative n/v
4 examples of serotonin blocker drugs
- dolasetron (Anzemet)
- granisetron (Kytril)
- ondansetron (Zofran)
- palonosetron (Aloxi)
MOA of tetrahydrocannabinoids (THC)
- major psychoactive substance in marijuana
- inhibitory effects on reticular formation, thalamus, cerebral cortex
- alter mood and body’s perception of its surroundings
Indications of tetrahydrocannabinoids
N/V associated with chemo, and anorexia associated with weight loss in AIDS/cancer pts
-may also stimulate appetite
Example of tetrahydrocannabinoid drug
dronabinol (Marinol)
Common adverse effects
- dizziness, h/a
- drowsiness, sedation, fatigue
- disorientation, confusion
- dry mouth, blurred vision, dilated pupils, urinary retention
for other specific adverse effects, use table 52-5 on page 831. btw there’s a lot.
Ginger: used for, adverse effects, and interactions
used for: n/v, caused by chemo, morning sickness, and motion sickness
adverse: anorexia, n/v, skin reactions
drug interactions: increase absorption of oral meds, increase bleeding risk with anticoagulants, not recommended during pregnancy
Nursing implications: what to assess?
N/V history, including causes
assess allergies, current meds (everything, literally everything), contraindications, potential drug interactions
Do antidiabetic/antiemetic drugs cause drowsiness?
Many of them do!
Warn pt’s about driving
Taking antiemetics with alcohol can cause __________
severe CNS depression
When are antiemetics given for chemo?
30-60 minutes before chemo begins
What must we monitor for?
therapeutic and adverse effects
What must be taught to pts?
change position slowly (avoid hypotensive effects) and VS frequently