Menu Close

Understanding Palliative Care: Nausea and Vomiting

Causes of Nausea

  • Chemical etiology
    • As a result of chemical triggers detected at the chemoreceptor trigger zone
    • Differential includes
      • Medications and drugs – opioids, antibiotics, NSAIDs
      • Chemotherapy
      • Metabolic causes such as kidney/liver failure
      • Electrolyte imbalance
  • Visceral
    • Differential includes
      • Bowel obstruction
      • Constipation
      • Liver capsule stretch due to metastatic disease
      • Anything that increases abdominal pressure
        • Ascites
        • Intra-abdominal masses/metastases
        • GERD
        • Delayed gastric emptying
  • Cerebral cortex
    • CNS lesion
    • Increased ICP
    • Head trauma
    • Psychogenic/anticipatory
  • Vestibular
    • Motion sickness
    • Positional vertigo

Management of Nausea

  • Choice of anti-emetic should be determined by the underlying cause of nausea
  • Gut prokinetic anti-emetics
    • Metoclopramide (acts on CTZ)
    • Domperidone – similar to metoclopramide but doesn’t cross BBB
  • Antipsychotics
    • Haloperidol (acts on D2 receptors at CTZ)
    • Prochloperazine
    • Olanzapine
    • Methotrimeprazine
      • Second-line, not first-line due to widespread receptor effect leading to more side effects
  • 5HT3 antagonists
    • Ondansetron (expensive in outpatient)
    • Granisetron
    • Mainly used for chemotherapy and radiotherapy induced nausea
  • Antihistamine
    • Dimenhydrinate (gravol)
    • Affects H1 histamine receptor
    • Most effective for vestibular nausea

Main anti-emetics used depending on cause of vomiting (from A practical approach to Symptom management in palliative care)

  • Drug toxin or metabolic
    • Haloperidol
    • Levomepromazine
  • Radiotherapy
    • Haloperidol
  • Chemotherapy
    • Ondansetron
    • Dexamethasone
    • Metoclopramide
  • Bowel obstruction
    • Cyclizine (antihistamine)
    • Scopomaline (anticholinergic)
  • Delayed gastric emptying
    • Metoclopramide
    • Domperidone
  • Raised intracranial pressure
    • Cyclizine
    • Dexamethasone