What is the best course of treatment for an 18-month-old child with diarrhea?

Management of Diarrhea in an 18-Month-Old Child

The best treatment for an 18-month-old child with diarrhea is oral rehydration therapy (ORT) using reduced osmolarity oral rehydration solution (ORS), which should be administered as first-line therapy for preventing and treating dehydration. 1, 2

Assessment of Dehydration

• Evaluate the degree of dehydration by examining skin turgor, mucous membranes, mental status, pulse, and capillary refill time 1
• Categorize dehydration as:
  • Mild (3-5% fluid deficit)
  • Moderate (6-9% fluid deficit)
  • Severe (≥10% fluid deficit, shock, or pre-shock) 1, 2
• Thirst is an early sign of dehydration in an infant, along with delayed capillary filling, absence of tears, and mucosal dryness 3

Rehydration Protocol

• For mild dehydration (3-5% fluid deficit): administer 50 ml/kg of ORS over 2-4 hours 1, 2
• For moderate dehydration (6-9% fluid deficit): administer 100 ml/kg of ORS over 2-4 hours 1, 2
• For severe dehydration (≥10% fluid deficit): immediate intravenous rehydration with isotonic fluids until pulse, perfusion, and mental status normalize, then transition to oral rehydration 1, 2

Administration Technique for ORT

• For children with vomiting, administer small volumes of ORS (5-10 mL) every 1-2 minutes, with a gradual increase in the amount consumed 4
• Use a spoon, syringe, cup, or feeding bottle to administer small amounts of ORS 4
• A common mistake is allowing a thirsty child to drink large volumes of ORS (ad libitum), which may worsen vomiting 4

Maintenance and Ongoing Losses

• After rehydration, replace ongoing losses with 10 ml/kg of ORS for each watery stool and 2 ml/kg of ORS for each episode of vomiting 1, 2
• Continue maintenance fluids until diarrhea and vomiting resolve 1
• Beverages such as cola drinks are inappropriate for rehydration, as they contain too little sodium and are excessively hyperosmolar, which may worsen diarrhea 3

Nutrition During Diarrhea

• Continue breastfeeding throughout the diarrheal episode 1, 2
• Resume age-appropriate diet during or immediately after rehydration 1, 2
• Early refeeding with milk or food after rehydration does not prolong diarrhea; evidence suggests it may reduce the duration of diarrhea by approximately half a day 5

Adjunctive Therapies

• Zinc supplementation is recommended for children 6 months to 5 years of age who live in countries with high zinc deficiency prevalence or who show signs of malnutrition 1, 2
• Ondansetron may be given to children >4 years of age to facilitate oral rehydration when vomiting is present, but is not recommended for an 18-month-old 1, 2
• Antimotility drugs (like loperamide) are contraindicated in children under 18 years of age 1, 6

Warning Signs Requiring Immediate Medical Attention

• Bloody diarrhea (dysentery), which may require antimicrobial treatment 4
• Severe dehydration with shock or near shock 4
• Intractable vomiting that prevents successful oral rehydration 4
• High stool output (>10 mL/kg/hour) 4
• Signs of glucose malabsorption (increased stool output with ORS administration) 4

Follow-up and Monitoring

• Reassess hydration status after 2-4 hours of rehydration 1
• Monitor for signs of improvement or deterioration 1
• Ensure parents understand the importance of continuing ORT and appropriate feeding 3