Management of Acute Diarrhea

Initial Assessment

The Centers for Disease Control and Prevention recommends assessing dehydration severity using clinical signs, including mild dehydration (3-5% fluid deficit) characterized by slightly dry mucous membranes, normal mental status, and normal skin turgor 1
Moderate dehydration (6-9% fluid deficit) is characterized by dry mucous membranes, sunken eyes, decreased skin turgor, and reduced urine output, according to the Centers for Disease Control and Prevention 1
Severe dehydration (≥10% fluid deficit) is a medical emergency requiring immediate attention, characterized by severe lethargy or altered consciousness, prolonged skin tenting, cool extremities, decreased capillary refill, and rapid deep breathing indicating acidosis, as stated by the Centers for Disease Control and Prevention 1
Key clinical indicators, such as prolonged skin retraction time, decreased perfusion, and rapid deep breathing, are more reliable predictors of dehydration than sunken fontanelle or absence of tears, according to the Centers for Disease Control and Prevention 1
Measuring body weight is essential to quantify fluid deficit and monitor response to therapy, as recommended by the Centers for Disease Control and Prevention 1
Stool cultures are indicated only for dysentery (bloody diarrhea), not for routine watery diarrhea in immunocompetent patients, according to the Centers for Disease Control and Prevention 1

For mild dehydration (3-5% deficit), the Centers for Disease Control and Prevention recommends administering 50 mL/kg of ORS containing 50-90 mEq/L sodium over 2-4 hours 2
For moderate dehydration (6-9% deficit), the Centers for Disease Control and Prevention suggests administering 100 mL/kg of ORS over 2-4 hours using the same small-volume technique 2
Severe dehydration (≥10% deficit) requires immediate IV rehydration with 20 mL/kg boluses of Ringer's lactate or normal saline until pulse, perfusion, and mental status normalize, as stated by the Centers for Disease Control and Prevention 2

The Centers for Disease Control and Prevention recommends replacing ongoing losses by administering 10 mL/kg of ORS for each watery or loose stool 1
Administering 2 mL/kg of ORS for each episode of vomiting is also recommended by the Centers for Disease Control and Prevention 1
If losses can be measured accurately, giving 1 mL of ORS for each gram of diarrheal stool is suggested by the Centers for Disease Control and Prevention 1

The American Academy of Pediatrics recommends that breastfed infants continue nursing on demand without interruption 2
Bottle-fed infants should resume full-strength, lactose-free or lactose-reduced formula immediately upon rehydration, as recommended by the American Academy of Pediatrics 2
Older children should resume age-appropriate normal diet immediately after rehydration, according to the Centers for Disease Control and Prevention 3
Early feeding is safer and more effective than delayed feeding, promoting intestinal cell renewal and preventing nutritional consequences, as stated by the Centers for Disease Control and Prevention 3

The World Health Organization states that antibiotics are NOT indicated for typical acute watery diarrhea 4
Loperamide should not be used in children under 18 years, according to pediatric guidelines 4
In adults, loperamide 2 mg may be used cautiously for symptom relief, but it is contraindicated if fever or bloody diarrhea develops, as recommended by the World Health Organization 4