Management of Recurrent Vomiting

Immediate Assessment and Diagnostic Workup

The American College of Gastroenterology recommends obtaining complete blood count, serum electrolytes, glucose, liver function tests, lipase, and urinalysis to exclude metabolic causes and assess for dehydration in patients with recurrent vomiting 1
Prolonged vomiting causes hypokalemia, hypochloremia, and metabolic alkalosis that require correction, according to the National Comprehensive Cancer Network 1

The National Comprehensive Cancer Network recommends initiating dopamine receptor antagonists as first-line treatment, such as metoclopramide, prochlorperazine, or haloperidol, titrated to maximum benefit and tolerance 1
The Journal of the National Comprehensive Cancer Network suggests using around-the-clock administration rather than PRN dosing for better control, with the oral route may not be feasible due to ongoing vomiting, and therefore, rectal or IV therapy is often required 2, 3
The American Gastroenterological Association recommends adding a 5-HT3 antagonist such as ondansetron if symptoms persist after 4 weeks of dopamine antagonist therapy, with monitoring for QTc prolongation when using ondansetron, especially in combination with other QT-prolonging agents 1

The American College of Gastroenterology recommends ensuring adequate hydration with at least 1.5 L/day fluid intake and correct any electrolyte abnormalities identified on laboratory testing, with addressing hypokalemia and hypomagnesemia specifically 1

The National Comprehensive Cancer Network suggests performing one-time esophagogastroduodenoscopy (EGD) or upper GI imaging to exclude obstructive lesions, with avoiding repeated endoscopy or imaging studies unless new symptoms develop 1

The American Academy of Pediatrics recommends monitoring for extrapyramidal symptoms with dopamine antagonists, particularly in young males, with never using antiemetics in suspected mechanical bowel obstruction, as this can mask progressive ileus and gastric distension 1