L4 Therapeutics for Nausea and Vomiting Flashcards
Vomiting is stimulated by the vomiting center of the _______________!
- ____________________ (motion sickness)
- ____________________(anticipatory/psychogenic)
Vomitting is stimulated by the vomiting center of medulla oblongata!!
- Vestibular apparatus (motion sickness)
- Cerebral cortex (anticipatory/psychogenic)
________________: suited for anticipatory Emesis (relaxes patient relieving psychological causes)
________________: Suited for Delayed emesis
Benzodiazepine: suited for anticipatory Emesis (relaxes patient relieving psychological causes)
Dexamethasone: Suited for Delayed emesis
Central vs. Peripheral inducers of emesis in Chemotherapy?
Central: Chemoreceptor Trigger Zone (CTZ) sits outside blood Brain barrier => activates Vomiting Center (Medulla Oblingata)
Peripheral: Serotonin (5HT) released from enterochromaffin cells in the gut
Receptors Regulating Nausea and Vomiting?
ACh (Hystocine Targets)
H1 - histamine (Cyclyzine/Promethazine Target)
5HT2 - serotonin (Ondansetron)
Dopamine (Metoclopramide, Domperidone, Haloperidol)
Anticholinergic Antiemetics
Drug(s)?
MOA?
Indication?
Side Effects?
Hyocine: Inhibits muscarinic neurotransmission to the vomiting center from Vestibular centers and Gut
Used For:
- Motion Sickness
- Post Operative Nausea and vomiting (PONV)
- Inhibition of saliva pre-operatively
Side Effects: Drowsiness, Dry mouth, Urinary retention, Blurred vison/Dilated pupils
Anti-Histamine Antiemetics
Drug(s)?
MOA?
Indication?
Side Effects?
Cyclizine: FIRST LINE for Drug-induced Vomiting and PONV
Promethazine: FIRST LINE IN PREGNANCY
MOA: Block H1 Receptor (Promethazine also Muscarinic + 5HT)
Side Effects:
- Sedation (esp Promethazine as it can pass BBB)
- Antimuscarinic => dry mouth, urinary retention
Dopamine Antiemetics
Drug(s)?
MOA?
Indication?
Side Effects?
Phenothiazines_ : Prochlorperazine, Perphenazine
Butyrophenone: Haloperidol
Benzamides: Metoclopramide, Domperidone
MOA: Non-Selective dopamine antagonists block Receptors abundant throughout the Chemoreceptor trigger zone (CTZ) and Vomiting Center
Indication: Most effective against Sevre N/V caused by direct stimulation of CTZ
Side Effects
- Prokinetic: gets GI tract moving => less bloating/stagnation can alleviate a lot of nausea/emesis
- Dopamine blockers => Parkinson like symptoms + Can lactate
5-HT Antagonists
Drug(s)?
MOA?
Indication?
Side Effects?
(-setron): Ondansetron; Granisetron; Palonosetron
MOA: Blocks 5-HT3 receptors in gut, CTZ and vomiting center: Free radicals cause the release of large amounts of 5-HT from gastric enterochromaffin cells
Indication: FIRST LINE FOR CHEMOTHERAPY. Also Prophylactically when vomiting is dangerous
Side Effects Ondansetron prolongs Q-T interval (risky if underlying arrhythmia)
Neurokokini-1 Antagonists
Drug(s)?
MOA?
Indication?
Side Effects?
(-itant): Aprepitant, Fosaprepitant, Rolapitant
MOA: Inhibit action of neurokinin at NK1 receptor
Indication: Used in conjunction w/ 5HT antagonists and steroids to augments effects of 5-HT3 antagonists and steroid in preventing (NOT TREATNG) Cisplatin (chemo-drug) induced emesis
_Side Effects: Hiccups, Anorexia, Extensive drug interactions
Corticosteroids for Nassau/Vomitting
Drug(s)?
MOA?
Indication?
(-asone): Dexamethasone and Prednisolone
MOA: Exert weak anti-emetics but produce synergistic effects with 5HT3 antagonists (Ondansetron) or Dopamine Antagnonist (Metoclopramide)
Indication: Suited for Delayed N/V. Dexamethasone given iv prior to chemo
Benzodiazepines
Drug(s)?
MOA?
Indication?
(-epam): Lorazepam, Diazepam
Suited for ANTICIPATORY N/V
- produces amnesia & sedation
- relaxes patient relieving psychological causes
ALL antiemetics have a more pronounced effect on ________ than ________
ALL DRUGS have a more pronounced effect on vomiting than nausea
Drug choice for motion sickness?
Hyoscine (Anti ACh)
Drug choice for Post-Operative Nausea and Vomiting (PONV)?
Cyclizine (Anti Histamine)
Hyocine (Anti-ACh)
Metoclopramide/Domperidone/Prochlorophernazine (Dopamine Antagonists)
Ondansetron (5HT3 Antagonist)
Drug choice for Drug-Induced Vomiting?
Cyclizine (esp. for opioid-induced vomiting)