What treatment should be given to a 10-year-old, 21kg male child with food poisoning, presenting with vomiting, pyrexia, anorexia, and epigastric pain?

Management of Food Poisoning in a 10-Year-Old Child with Vomiting, Fever, and Epigastric Pain

For this child with suspected food poisoning presenting with one episode of vomiting, low-grade fever (100°F), anorexia, and epigastric pain, oral rehydration therapy is the primary treatment, with ondansetron (0.15-0.2 mg/kg oral, maximum 4-8 mg) indicated if persistent vomiting prevents oral intake. 1, 2, 3

Immediate Assessment Priorities

Check for red flag signs that require urgent intervention:

• Assess vital signs for tachycardia ≥110 bpm, fever ≥38°C (100.4°F), or hypotension which predict serious pathology 1, 4
• Examine for peritoneal signs (abdominal rigidity, rebound tenderness, absent bowel sounds) suggesting perforation with 30% mortality if delayed 1, 5
• Evaluate hydration status: decreased peripheral perfusion, abnormal skin turgor, abnormal respiratory pattern, and weight loss percentage 6, 7
• Look for bilious or bloody vomiting, altered sensorium, toxic appearance, or severe dehydration 3

This child's presentation (single vomiting episode, 100°F fever, no diarrhea yet) suggests early viral gastroenteritis or food poisoning without current severe dehydration. 8, 9

Primary Treatment: Oral Rehydration Therapy

Oral rehydration solution (ORS) is the mainstay of treatment and equally efficacious as IV rehydration for mild-moderate dehydration:

• Begin ORS immediately at home with small, frequent volumes (5 mL every minute initially via spoon or syringe) 8
• Replace ongoing losses: give appropriate volumes of ORS for each episode of vomiting or diarrhea 8
• Continue age-appropriate diet immediately upon rehydration—do not withhold food 8
• For a 21 kg child, maintenance fluid needs are approximately 1,500 mL/day plus replacement of ongoing losses 8

The evidence strongly supports early feeding rather than "gut rest"—fasting reduces enterocyte renewal and increases intestinal permeability. 8

Antiemetic Therapy: Ondansetron

Ondansetron is indicated when persistent vomiting prevents oral intake:

• Dosing for this 21 kg child: Ondansetron 0.15-0.2 mg/kg oral = 3-4 mg oral (can round to 4 mg), may repeat every 4-6 hours 1, 10, 3
• Alternative: 0.15 mg/kg IV (3 mg IV) if unable to tolerate oral, maximum 4 mg per dose 10, 3
• Ondansetron reduces vomiting, facilitates oral rehydration, minimizes need for IV hydration and hospitalization 2, 6
• Mean ED stay is reduced and serious side effects are rare 2, 6

Critical safety considerations for ondansetron:

• Obtain baseline ECG before administration due to dose-dependent QT prolongation risk 1, 10
• Avoid in congenital long QT syndrome 10
• Monitor for serotonin syndrome if used with other serotonergic drugs (SSRIs, SNRIs, tramadol, fentanyl) 10
• Watch for hypersensitivity reactions including anaphylaxis and bronchospasm 10

IV Therapy: When and What to Give

IV fluids are NOT routinely needed for this presentation but are indicated if:

• Child cannot tolerate oral fluids despite ondansetron 8, 6
• Signs of severe dehydration (>5% weight loss, abnormal capillary refill, abnormal skin turgor) 6, 7
• Persistent vomiting with inability to maintain hydration 3, 6

If IV access is required:

• Use isotonic crystalloid (normal saline or lactated Ringer's) for rehydration 8
• Bolus 20 mL/kg over 1 hour for moderate dehydration, repeat as needed 8
• Transition to oral rehydration as soon as tolerated 8, 6

Medications NOT Indicated

Do NOT give:

• Antibiotics—not indicated for acute gastroenteritis unless dysentery, high fever, or watery diarrhea >5 days 8
• Antidiarrheal agents—not indicated in children with acute gastroenteritis 8, 7
• Routine antiemetics other than ondansetron—many experts discourage routine use, but ondansetron has proven efficacy 6, 7

Empiric Acid Suppression: Consider if Symptoms Persist

If epigastric pain persists beyond initial viral gastroenteritis treatment or peptic pathology is suspected:

• Start high-dose PPI: omeprazole 1 mg/kg/day (approximately 20 mg once daily for this 21 kg child), maximum 40 mg 1, 4, 5
• Healing rates are 80-90% for duodenal ulcers and 70-80% for gastric ulcers 1, 5

Red Flags Requiring Urgent Evaluation

Seek immediate medical attention if:

• Persistent vomiting despite ondansetron (suggests disorder beyond functional dyspepsia) 1, 4
• Bilious or bloody vomiting 3
• Peritoneal signs develop 1, 5
• Hemodynamic instability 4
• Altered mental status 3
• Symptoms persist beyond 8 weeks with epigastric tenderness 1

Dietary Management

Continue age-appropriate diet immediately:

• Offer starches, cereals, yogurt, fruits, and vegetables 8
• Avoid foods high in simple sugars and fats 8
• Replace excess fluid losses with ORS 8

Common Pitfalls to Avoid

• Do not withhold food—early feeding improves outcomes 8
• Do not use "gut rest" approach—fasting is harmful 8
• Do not give IV fluids routinely when oral rehydration is feasible 8, 6
• Do not use antibiotics empirically for uncomplicated gastroenteritis 8
• Do not dismiss cardiac causes if symptoms are atypical or severe—obtain ECG if concerned 4, 5