What is the treatment for acute gastroenteritis?

Treatment of Acute Gastroenteritis

Oral rehydration therapy (ORT) is the first-line treatment for mild to moderate dehydration in acute gastroenteritis for both children and adults, with intravenous fluids reserved for severe cases. 1, 2

Assessment of Hydration Status

• Evaluate hydration status through physical examination looking for specific signs of dehydration: decreased skin turgor, dry mucous membranes, sunken eyes, altered mental status, tachycardia, and decreased urine output 1
• Categorize dehydration as:
  • Mild: <4% body weight lost (3-5%)
  • Moderate: 4-6% body weight lost (6-9%)
  • Severe: >6% body weight lost (≥10%) 1, 2

Rehydration Protocol

Mild to Moderate Dehydration

• Administer oral rehydration solution (ORS) at the following doses:
  • Infants and children: 50-100 mL/kg over 3-4 hours 1
  • Adolescents and adults: 2-4 L of ORS 1
• Use commercially available low-osmolarity ORS (e.g., Pedialyte, CeraLyte) 1
• Avoid inappropriate fluids like apple juice, sports drinks (Gatorade), or soft drinks as they can exacerbate diarrhea through osmotic effects 1, 2
• For children who refuse ORS, consider nasogastric administration at 50-100 mL/kg over 3-4 hours 1, 2

Severe Dehydration

• Administer isotonic intravenous fluids (lactated Ringer's or normal saline) at 20 mL/kg over 30 minutes 1
• Continue IV rehydration until pulse, perfusion, and mental status normalize (typically 2-4 hours) 1, 2
• Transition to oral rehydration once the patient improves 2

Maintenance and Ongoing Losses

• Replace ongoing losses with ORS until diarrhea and vomiting resolve:
  • Children <10 kg: 60-120 mL ORS for each diarrheal stool/vomiting episode (up to ~500 mL/day) 1
  • Children >10 kg: 120-240 mL ORS for each diarrheal stool/vomiting episode (up to ~1 L/day) 1
  • Adolescents and adults: ad libitum intake up to ~2 L/day 1

Nutritional Management

• Continue breastfeeding throughout the diarrheal episode in infants 1, 2
• Resume age-appropriate diet during or immediately after rehydration 1, 2
• Avoid fasting or withholding food for 24 hours as this does not improve outcomes 1, 2

Pharmacological Management

Antiemetics

• Consider ondansetron in children >4 years and adolescents with significant vomiting to facilitate oral rehydration (0.15 mg/kg per dose) 1, 2
• Ondansetron can decrease the need for IV fluids and hospitalization 3

Antidiarrheals

• Loperamide may be given to immunocompetent adults with acute watery diarrhea (4 mg initially, followed by 2 mg after each loose stool) 1, 2
• Do not use loperamide in children <18 years 2
• Avoid loperamide in elderly patients taking drugs that can prolong the QT interval (e.g., Class IA or III antiarrhythmics) 4
• Avoid antimotility agents in cases of inflammatory diarrhea, bloody diarrhea, diarrhea with fever, or suspected toxic megacolon 1, 2

Antimicrobials

• Antimicrobial agents have limited usefulness since viral agents are the predominant cause of acute gastroenteritis 2
• Consider antimicrobial therapy only in specific cases such as bloody diarrhea, recent antibiotic use, exposure to certain pathogens, recent foreign travel, or immunodeficiency 2

Prevention Measures

• Practice proper hand hygiene after using toilet, changing diapers, before/after food preparation, and after handling animals 1, 2
• Use infection control measures including gloves, gowns, and hand hygiene with soap and water or alcohol-based sanitizers when caring for patients with diarrhea 1, 2
• Separate ill persons from well persons until at least 2 days after symptom resolution 2

Common Pitfalls to Avoid

• Delaying rehydration therapy while awaiting diagnostic testing 2
• Using inappropriate fluids like apple juice or sports drinks for rehydration 1, 2
• Administering antimotility drugs to children or in cases of bloody diarrhea 2, 4
• Unnecessarily restricting diet during or after rehydration 1, 2
• Relying on antidiarrheal agents rather than appropriate fluid, electrolyte, and nutritional therapy 2