Treatment of Nausea
For general nausea treatment, a stepwise approach is recommended, starting with dopamine receptor antagonists (e.g., metoclopramide 10-20 mg PO/IV every 4-6 hours) as first-line therapy, followed by 5-HT3 receptor antagonists (e.g., ondansetron 8 mg PO/IV every 8 hours) as second-line therapy. 1
Assessment and Etiology
Before initiating treatment, identify potential causes of nausea:
- Medication-induced: digoxin, phenytoin, carbamazepine, tricyclic antidepressants
- Gastrointestinal: constipation, bowel obstruction, gastroparesis
- CNS involvement: brain metastases, meningeal disease
- Metabolic: hypercalcemia, dehydration, electrolyte abnormalities
- Psychogenic: anxiety, eating disorders, somatization
First-Line Treatment Options
Dopamine Receptor Antagonists
- Metoclopramide: 10-20 mg PO/IV every 4-6 hours
- Haloperidol: 0.5-2 mg PO/IV every 4-6 hours
- Prochlorperazine: 10 mg PO/IV every 6 hours or 25 mg PR every 12 hours
- Promethazine: 12.5-25 mg PO/IV every 4-6 hours or 25 mg PR every 6 hours
Anticholinergic Agents
- Meclizine: 25 mg PO every 6 hours (particularly effective for vestibular-related nausea)
- Scopolamine: 1.5 mg transdermal patch every 72 hours
Second-Line Treatment Options
5-HT3 Receptor Antagonists
- Ondansetron: 8 mg PO/IV every 8 hours (particularly effective for chemotherapy-induced nausea) 2, 3
- Granisetron: 1-2 mg PO daily or 1 mg PO twice daily
- Dolasetron: 100 mg PO daily
Corticosteroids
- Dexamethasone: 4-8 mg PO/IV daily (particularly effective as adjunctive therapy) 4
Breakthrough or Refractory Nausea
For breakthrough nausea, add one agent from a different drug class to the current regimen 4:
- Olanzapine: 5-10 mg PO daily (category 1 evidence for breakthrough treatment) 4
- Lorazepam: 0.5-2 mg PO/SL/IV every 6 hours
- Cannabinoids: Dronabinol 5-10 mg PO every 4-6 hours or Nabilone 1-2 mg PO twice daily
Special Considerations
Chemotherapy-Induced Nausea and Vomiting (CINV)
For highly emetogenic chemotherapy:
- Three-drug combination: NK1 receptor antagonist + 5-HT3 receptor antagonist + dexamethasone 4
For moderately emetogenic chemotherapy:
- Two-drug combination: Palonosetron (day 1) + dexamethasone (days 1-3) 4
Radiation-Induced Nausea and Vomiting
- For high-risk radiation: 5-HT3 antagonist before each fraction + dexamethasone for 5 days 4
- For moderate-risk radiation: 5-HT3 antagonist before each fraction (dexamethasone optional) 4
Non-Pharmacological Management
- Dietary modifications: small, frequent meals; low-fat diet if tolerated; avoiding trigger foods
- Adequate hydration
- Discontinuing unnecessary medications
- Acupressure wristbands
- Ginger supplements
Monitoring and Adjustment
- Daily evaluation of vomiting frequency and characteristics
- Monitor hydration and electrolyte levels
- Adjust antiemetic regimen according to patient response
- Monitor for adverse effects:
- QT prolongation with ondansetron and haloperidol (caution in cardiac patients)
- Extrapyramidal symptoms with dopamine antagonists
- Sedation with promethazine and lorazepam
Red Flag Symptoms Requiring Urgent Evaluation
- Hematemesis
- Severe abdominal pain
- Focal neurological findings
- Weight loss or malnutrition
- Concern for mechanical obstruction
By following this algorithmic approach to nausea management, clinicians can effectively control symptoms while minimizing adverse effects and addressing underlying causes.