Management of Severe Diarrhea

Immediate Assessment and Rehydration

The Centers for Disease Control and Prevention recommends immediately initiating intravenous rehydration with Ringer's lactate or normal saline at 20 mL/kg boluses until pulse, perfusion, and mental status normalize, then transitioning to oral rehydration solution (ORS) to complete fluid replacement in patients with severe diarrhea and signs of shock 1, 2
The World Health Organization suggests classifying dehydration as mild (3-5% fluid deficit), moderate (6-9% fluid deficit), or severe (≥10% fluid deficit, shock, or pre-shock state) 2
Severe dehydration is a medical emergency that requires immediate attention, with administration of 20 mL/kg IV boluses of Ringer's lactate or normal saline 1, 2

For moderate dehydration, the American Academy of Pediatrics recommends administering 100 mL/kg of ORS containing 50-90 mEq/L sodium over 2-4 hours 2, 3
For mild dehydration, the American Academy of Pediatrics suggests administering 50 mL/kg of ORS over 2-4 hours 2, 3

The Centers for Disease Control and Prevention recommends replacing ongoing stool and vomit losses throughout treatment, with 10 mL/kg of ORS for each watery or loose stool and 2 mL/kg of ORS for each vomiting episode 1, 2

The World Health Organization suggests using reduced-osmolarity ORS (245 mmol/L total osmolarity) containing 50-90 mEq/L sodium 2, 3

The Centers for Disease Control and Prevention recommends administering small, frequent volumes of ORS initially (5 mL every minute) to patients who are vomiting 1

The American Academy of Pediatrics suggests continuing breastfeeding on demand throughout illness for breastfed infants, and resuming full-strength, lactose-free or lactose-reduced formula immediately after rehydration for formula-fed infants 1, 3
The American Academy of Pediatrics recommends resuming regular diet with easily digestible foods (starches, cereals, yogurt, fruits, vegetables) for older children and adults 1, 2

The Centers for Disease Control and Prevention recommends considering antibiotics when bloody diarrhea (dysentery) or high fever is present, watery diarrhea persists >5 days, or stool cultures, microscopy, or epidemic setting indicate a treatable pathogen 1, 2

The American Academy of Pediatrics suggests not delaying rehydration while awaiting diagnostic results, and starting ORS immediately 2
The Centers for Disease Control and Prevention recommends not using plain water, juice, or sports drinks for rehydration, as these lack appropriate sodium concentration 1
The American Academy of Pediatrics suggests not allowing ad libitum drinking of large ORS volumes in thirsty patients, as this worsens vomiting 4

The American Academy of Pediatrics recommends reassessing hydration status after 2-4 hours of rehydration 2, 3