What is the treatment for projectile vomiting?

Treatment of Projectile Vomiting

For projectile vomiting, use scheduled (around-the-clock) antiemetics rather than as-needed dosing, with metoclopramide or ondansetron as first-line agents, administered via IV or rectal routes if oral intake is not feasible due to ongoing vomiting. 1, 2

Route of Administration is Critical

• The oral route is typically not feasible with projectile vomiting; therefore, rectal or intravenous therapy is required. 1, 2
• Nasal spray formulations may provide acute delivery for breakthrough symptoms 1
• Once vomiting is controlled, transition to oral maintenance therapy 1

First-Line Pharmacologic Options

Dopamine Antagonists (Preferred for Gastric Motility Issues)

• Metoclopramide is the strongest evidence-based choice, particularly when gastric motility issues contribute to symptoms, as it blocks dopamine receptors in the chemoreceptor trigger zone and improves gastric emptying. 2, 3, 4
• Prochlorperazine is an effective alternative dopamine antagonist 2
• Haloperidol can be used for refractory cases 1, 2

Serotonin (5-HT3) Antagonists

• Ondansetron is highly effective for persistent vomiting, with superior efficacy and fewer side effects compared to other antiemetics. 2, 5, 6, 7, 8
• Ondansetron 4-8 mg IV/PO is appropriate for adults; 0.15 mg/kg IV (maximum 4 mg) for children 8
• Granisetron is an alternative 5-HT3 antagonist 1

Scheduled Dosing Strategy

• Around-the-clock administration of antiemetics is strongly recommended to prevent emesis, rather than PRN (as-needed) dosing. 1, 2
• Prevention is far more effective than treating established vomiting 2
• Multiple concurrent agents using different mechanisms may be necessary for severe cases 1

Adjunctive Therapies

• Corticosteroids (dexamethasone) can be incorporated for breakthrough treatment or refractory cases. 1
• Lorazepam may be added if anxiety is contributing to symptoms 1, 2
• Proton pump inhibitors or H2 blockers should be considered, as patients often have difficulty discriminating heartburn from nausea 1

Essential Supportive Care

• Ensure adequate hydration with isotonic fluid resuscitation (10-20 mL/kg boluses of normal saline as needed). 5
• Assess and correct electrolyte abnormalities, which can worsen nausea and vomiting. 1, 2, 5
• Consider nasogastric decompression only in ventilated patients with bilious vomiting, as it increases risk of aspiration in unsedated patients 5

Breakthrough Treatment Principle

• When initial antiemetic fails, add an agent from a different drug class rather than increasing the dose of the same medication. 1
• No single treatment is superior for managing breakthrough emesis; multiple agents with alternating schedules or routes may be required 1

Critical Red Flags Requiring Further Evaluation

• Bilious or bloody vomiting suggests surgical pathology (bowel obstruction, malrotation with volvulus). 5, 8
• Altered mental status, severe dehydration, or toxic appearance warrant immediate stabilization and diagnostic workup 8
• Consider brain metastases, electrolyte abnormalities, tumor infiltration of bowel, or other gastrointestinal pathology if vomiting persists despite treatment 1, 2
• Rule out gastroparesis, gastric outlet obstruction, or medication-induced causes (especially opioids) 2, 4

Common Pitfalls to Avoid

• Do not rely on oral medications when projectile vomiting is present—use parenteral or rectal routes. 1, 2
• Avoid PRN dosing; scheduled administration prevents recurrence more effectively 1, 2
• Be aware that metoclopramide carries risk of extrapyramidal symptoms (especially in patients <30 years old) and tardive dyskinesia with prolonged use beyond 12 weeks 3
• Document characteristics of emesis (coffee-ground appearance suggests upper GI bleeding requiring different management) 5