What is the recommended treatment and prescription for acute diarrhea?

Treatment of Acute Diarrhea

Oral rehydration solution (ORS) is the cornerstone of treatment for acute diarrhea, with reduced osmolarity ORS recommended as first-line therapy for mild to moderate dehydration in all age groups. 1

Initial Assessment

Evaluate dehydration severity by examining:

• Skin turgor, mucous membranes, mental status, pulse, and capillary refill time 1, 2
• Categorize as:
  • Mild (3-5% fluid deficit) 1
  • Moderate (6-9% fluid deficit) 1
  • Severe (≥10% fluid deficit, shock, or altered mental status) 1

Rehydration Strategy by Severity

Mild Dehydration (3-5% deficit)

• Administer 50 mL/kg of ORS over 2-4 hours 1, 2
• Use small volumes initially (one teaspoon) with gradual increase 1
• Reassess hydration status after 2-4 hours 1

Moderate Dehydration (6-9% deficit)

• Administer 100 mL/kg of ORS over 2-4 hours 1, 2
• Nasogastric administration may be considered if oral intake is not tolerated or child refuses to drink 1

Severe Dehydration (≥10% deficit)

• Immediate intravenous rehydration with isotonic fluids (lactated Ringer's or normal saline) is required 1
• Administer 20 mL/kg boluses until pulse, perfusion, and mental status normalize 1
• Continue IV fluids until patient awakens, has no aspiration risk, and no ileus 1
• Transition to ORS for remaining deficit once stabilized 1

Maintenance and Ongoing Loss Replacement

After rehydration, replace ongoing losses with:

• 10 mL/kg of ORS for each watery stool 1, 2
• 2 mL/kg of ORS for each episode of vomiting 1, 2
• Continue maintenance fluids until diarrhea and vomiting resolve 1

Nutrition During Illness

• Continue breastfeeding throughout the diarrheal episode 1, 2
• Resume age-appropriate usual diet during or immediately after rehydration 1
• For bottle-fed infants, use full-strength formula immediately upon rehydration 1

Adjunctive Therapies

Antimotility Agents

• Loperamide is CONTRAINDICATED in children <18 years of age 1, 3
• For adults: Loperamide may be given to immunocompetent adults with acute watery diarrhea 1
  • Initial dose: 4 mg (two capsules) followed by 2 mg after each unformed stool 3
  • Maximum daily dose: 16 mg (eight capsules) 3
• Avoid loperamide in bloody diarrhea, fever, or suspected inflammatory diarrhea at any age due to risk of toxic megacolon 1

Antiemetics

• Ondansetron may be given to children >4 years of age to facilitate oral rehydration when vomiting is present, but only after adequate hydration is achieved 1, 2

Probiotics

• May be offered to reduce symptom severity and duration in immunocompetent adults and children 1

Zinc Supplementation

• Recommended for children 6 months to 5 years of age who reside in countries with high zinc deficiency prevalence or who have signs of malnutrition 1, 2
• Reduces duration of diarrhea 1, 2

Antibiotic Therapy

Antibiotics are NOT routinely indicated for most acute diarrhea 1

Consider empiric antibiotics only for:

• Bloody diarrhea (dysentery) with fever or systemic toxicity 1
• Suspected enteric fever with sepsis 1
• Immunocompromised patients with severe illness 1

Avoid antibiotics in:

• STEC O157 and other Shiga toxin-producing E. coli infections 1

Critical Pitfalls to Avoid

• Do NOT allow thirsty children to drink large volumes of ORS ad libitum, as this worsens vomiting 2
• Do NOT use antimotility drugs in children under 18 years—risk of respiratory depression and cardiac complications 1, 3
• Do NOT withhold food or prolong fasting—this worsens nutritional status 2
• Do NOT use antiemetics, antidiarrheals, or spasmolytics as substitutes for fluid therapy 1

Warning Signs Requiring Immediate Medical Attention

• Bloody diarrhea with fever 2
• Severe dehydration with shock 2
• Intractable vomiting preventing oral rehydration 2
• High stool output (>10 mL/kg/hour) 2
• No clinical improvement after 48 hours 1