What is the recommended management for nausea and vomiting?

Management of Nausea and Vomiting

The recommended management for nausea and vomiting requires identifying the underlying cause and implementing targeted antiemetic therapy, with dopamine receptor antagonists (such as prochlorperazine, haloperidol, or metoclopramide) serving as first-line treatment for persistent symptoms. 1

Initial Assessment

• Evaluate for specific causes including chemotherapy/radiation-induced vomiting, severe constipation, gastroparesis, bowel obstruction, medication-induced vomiting, and metabolic abnormalities 1
• Assess timing, duration, and associated symptoms to distinguish between acute (≤7 days) and chronic (≥4 weeks) nausea and vomiting 2
• Screen for nausea and vomiting at initial outpatient and inpatient visits, especially in cancer patients 3
• For gastritis or gastroesophageal reflux, consider proton pump inhibitors or H2 receptor antagonists 1

Treatment Algorithm

First-Line Therapy

• Begin with dopamine receptor antagonists (prochlorperazine, haloperidol, metoclopramide) titrated to maximum benefit and tolerance 1, 3
• For chemotherapy-induced nausea and vomiting, provide prophylaxis based on the emetogenic potential of the chemotherapy regimen 3, 4
• For highly emetogenic chemotherapy, a single 24 mg oral dose of ondansetron has shown superior efficacy 4
• For moderately emetogenic chemotherapy, ondansetron 8 mg administered 30 minutes before chemotherapy, with a subsequent 8 mg dose 8 hours later, followed by 8 mg twice daily for 1-2 days 4

Second-Line Therapy

• If vomiting persists, add one or more of the following:
  • 5-HT3 receptor antagonists (ondansetron, granisetron) 1, 4
  • Anticholinergic agents 1
  • Antihistamines 1
  • Cannabinoids for refractory cases 1, 3
• For anxiety-related nausea, consider adding benzodiazepines (lorazepam) 1

Refractory Symptoms

• Consider adding corticosteroids 1, 3
• For intractable symptoms, continuous intravenous or subcutaneous infusion of antiemetics may be necessary 3
• Consider antipsychotics such as olanzapine for persistent symptoms 1, 3
• Alternative therapies like acupuncture may be beneficial in some cases 3

Special Populations

Cancer Patients

• Provide prophylaxis for acute and delayed emesis in patients receiving moderate to highly emetogenic chemotherapy 3
• Follow up after treatment to assess symptom control 3
• For patients with small bowel obstruction, special considerations are needed 3

Patients with Hepatic Impairment

• In patients with severe hepatic impairment (Child-Pugh score ≥10), do not exceed a total daily dose of 8 mg of ondansetron 4
• Clearance is reduced 2-3 fold and half-life increases to 20 hours in severe hepatic impairment 4

Non-Pharmacologic Management

• Ensure adequate fluid and electrolyte replacement 2
• Recommend small, frequent meals and avoidance of trigger foods 2
• For chronic nausea and vomiting, identify and address underlying causes such as gastroparesis or cyclic vomiting syndrome 5

Important Pitfalls to Avoid

• Avoid antiemetics in patients with suspected mechanical bowel obstruction 1
• Monitor for extrapyramidal side effects with dopamine receptor antagonists 1
• Be aware of QT prolongation risk with ondansetron, especially in patients with electrolyte abnormalities, congestive heart failure, or bradyarrhythmias 4
• Long-term use of benzodiazepines should be limited due to risk of dependence 1
• When using combination therapy, target different mechanisms of action for synergistic effect rather than replacing one antiemetic with another 1

Follow-Up

• For acute nausea and vomiting, use medications for the shortest time necessary to control symptoms 2
• For chronic symptoms, regular follow-up is essential to assess treatment efficacy and adjust therapy as needed 5
• Consider gastric emptying studies if gastroparesis is suspected in cases of chronic nausea and vomiting 6