What is the management for a 15-year-old female with abdominal pain, diarrhea, nausea, and vomiting without fever?

Management of Acute Gastroenteritis in an Adolescent

Begin oral rehydration solution (ORS) immediately at home using small, frequent volumes (5-10 mL every 1-2 minutes via spoon or syringe), gradually increasing as tolerated, which successfully rehydrates >90% of patients with vomiting and diarrhea without requiring antiemetic medication. 1

Immediate Rehydration Strategy

Assessment of Hydration Status

• Evaluate for clinical signs of dehydration: skin turgor, mental status, mucous membrane moisture, capillary refill, and vital signs 1
• Since all examinations are normal in this patient, she likely has no dehydration or mild dehydration (3-5% fluid deficit) 2, 1
• For patients without signs of dehydration, skip the rehydration phase and start maintenance therapy immediately 2

ORS Administration Protocol

• Administer 5-10 mL of ORS every 1-2 minutes using a spoon or syringe to prevent triggering more vomiting 1
• Gradually increase volume as tolerated without triggering vomiting 1
• Replace ongoing losses: give 10 mL/kg (approximately 370 mL for a typical 15-year-old) for each watery stool and 2 mL/kg (approximately 74 mL) for each vomiting episode 2, 1
• Continue ORS until diarrhea and vomiting resolve 1

Low-osmolarity ORS formulations are preferred over sports drinks or juices, as foods high in simple sugars (soft drinks, undiluted apple juice) can exacerbate diarrhea through osmotic effects 1

Nutritional Management

• Resume age-appropriate diet immediately during or after rehydration without withholding food 1
• Early refeeding reduces severity and duration of illness 1
• Recommended foods include starches, cereals, yogurt, fruits, and vegetables 2
• Avoid foods high in simple sugars and fats 2

Pharmacological Considerations

What NOT to Give

• Do NOT administer loperamide - it is contraindicated in patients <18 years with acute diarrhea 1, 3
• Do NOT use antimotility agents, adsorbents, antisecretory drugs, or toxin binders - they do not reduce diarrhea volume or duration 1
• Do NOT give empiric antibiotics - viral agents are the predominant cause, and antimicrobials have limited usefulness unless specific high-risk features develop (bloody diarrhea, fever ≥38.5°C with sepsis signs, recent foreign travel, immunocompromised state) 1

What MAY Be Considered

• Ondansetron may be given to facilitate oral rehydration if vomiting is significant and persistent, as the patient is >4 years old 1
• Probiotics may be offered to reduce symptom severity and duration by approximately 25 hours 1

Monitoring and Red Flags

• Reassess hydration status after 2-4 hours if rehydration was needed 2, 1
• Seek immediate medical care if:
  • Signs of severe dehydration develop (≥10% fluid deficit, altered mental status, shock) 2, 1
  • Bloody diarrhea appears 1
  • High fever develops 1
  • Decreased urine output, lethargy, or irritability occurs 1
  • No clinical improvement within 48 hours 1

Infection Control

• Practice proper hand hygiene after using toilet, before eating, and before food preparation 1
• Separate from well persons until at least 2 days after symptom resolution 1

Common Pitfalls to Avoid

• Do not delay rehydration while awaiting diagnostic testing - initiate ORS promptly 1
• Do not use inappropriate fluids (apple juice, sports drinks) as primary rehydration solutions 1
• Do not unnecessarily restrict diet during or after rehydration 1
• Do not administer antimotility drugs to adolescents or in cases of bloody diarrhea 1