Acute Gastroenteritis from Contaminated Oysters

Initial Management Strategy

• The American Society for Nutrition recommends maintaining adequate fluid intake of at least 1.5 L/day to prevent dehydration, which accounts for one-third of emergency room visits within 3 months of gastrointestinal illness 1, 2
• Monitor for signs of dehydration including decreased urine output, dizziness, dry mucous membranes, and tachycardia 1
• Small, frequent sips of clear fluids are better tolerated than large volumes 2

Antiemetic Therapy

• The American Gastroenterological Association recommends initiating metoclopramide 10 mg orally every 6-8 hours as first-line therapy for persistent vomiting, as it provides both antiemetic effects and promotes gastric emptying 2
• Add ondansetron 4-8 mg orally/sublingually if symptoms persist after 4 hours, though be aware this may increase diarrhea volume 2

When to Seek Medical Attention

• The American College of Gastroenterology recommends seeking immediate medical attention if signs of dehydration develop despite oral rehydration, such as decreased urine output, orthostatic hypotension, or altered mental status 1, 2
• Seek medical evaluation if severe abdominal pain or signs of peritonitis develop 3
• Seek medical evaluation if bloody diarrhea occurs 3

Special Considerations and Pitfalls

• The National Institute of Diabetes and Digestive and Kidney Diseases recommends thiamin supplementation if vomiting persists for >2-3 weeks to prevent Wernicke's encephalopathy 1, 2