Can ondansetron or domperidone reduce vomiting associated with rituximab (Rituxan) infusion?

Management of Vomiting Associated with Rituximab Infusion

Ondansetron is the recommended antiemetic agent for reducing vomiting associated with rituximab infusion, while domperidone is not specifically supported by guidelines for this indication. 1

Antiemetic Options for Rituximab-Associated Vomiting

5-HT3 Receptor Antagonists (First-Line)

• Ondansetron is a potent and selective 5-HT3 receptor antagonist with demonstrated efficacy in preventing chemotherapy-induced nausea and vomiting 2
• Recommended dosing for ondansetron:
  • Intravenous: 8 mg administered over 15 minutes prior to rituximab infusion 1
  • Oral: 8 mg three times daily, with first dose given at least 30 minutes before rituximab 2, 3
• Ondansetron has shown complete response rates (no vomiting) of up to 60% in patients receiving highly emetogenic chemotherapy 4

Corticosteroids (Adjunct Therapy)

• Adding dexamethasone to ondansetron significantly enhances antiemetic efficacy 1
• Recommended dexamethasone dosing:
  • Intravenous: 8-20 mg single dose before rituximab infusion 1
  • Can be continued orally for delayed emesis if needed 1

Dopamine Antagonists (Alternative/Adjunct)

• While domperidone is a dopamine antagonist that can be used for chemotherapy-induced nausea and vomiting, it is not specifically recommended for rituximab-associated emesis 1
• Dopamine antagonists are generally considered less effective than 5-HT3 antagonists for chemotherapy-induced vomiting 1
• If used, domperidone typical dosing is 20 mg orally 3-4 times daily 1

Algorithm for Managing Rituximab-Associated Vomiting

1. Pre-medication (Primary Prevention):

   • Administer ondansetron 8 mg IV 30 minutes before rituximab infusion 1
   • Add dexamethasone 8-20 mg IV (dose depends on overall emetogenic potential of full regimen) 1

2. Maintenance (During and After Infusion):

   • Continue with oral ondansetron 8 mg every 8 hours for 1-2 days as needed 2, 3
   • For delayed nausea/vomiting, continue dexamethasone twice daily if needed 1

3. Breakthrough Vomiting:

   • Add a medication from a different class (e.g., dopamine antagonist like metoclopramide) 1
   • Consider lorazepam 1-2 mg for added anxiolytic effect if anticipatory nausea/vomiting develops 1

Important Considerations and Caveats

• Cardiac Safety: High-dose ondansetron (32 mg IV) has been associated with QT interval prolongation. Lower doses used for rituximab-associated vomiting appear safer 5

• Cost-Effectiveness: Consider switching to metoclopramide in patients who have mild or no vomiting with ondansetron during first cycle, which can reduce costs by approximately 47% 6

• Common Side Effects:

  • Ondansetron: Headache (10% of treatment cycles) and constipation (30% of treatment cycles) 6
  • Domperidone: Extrapyramidal symptoms (5% of patients) 6

• Anticipatory Nausea/Vomiting: For patients developing anticipatory symptoms, benzodiazepines like lorazepam (1-2 mg) may be beneficial 1

• Refractory Cases: For patients with inadequate control, consider adding a medication from a different class or switching to a different 5-HT3 antagonist 1