What is the appropriate diet for a patient with ongoing diarrhea?

Dietary Management for Ongoing Diarrhea

For patients with ongoing diarrhea, resume an age-appropriate regular diet immediately after rehydration, focusing on starches (rice, potatoes, noodles, crackers, bananas), cereals, yogurt, vegetables, and fresh fruits, while strictly avoiding foods high in simple sugars and high-fat foods. 1, 2

Immediate Dietary Approach

The BRAT diet (Bananas, Rice, Applesauce, Toast) combined with bland foods should be initiated as soon as rehydration begins—do not withhold food. 3, 1, 2 Early realimentation prevents malnutrition and may actually reduce stool output rather than worsen diarrhea. 2, 4

Foods to Include:

• Starches: Rice, potatoes, noodles, crackers, bananas, plain pasta 1, 4
• Cereals: Rice cereal, wheat cereal, oat cereal 1
• Yogurt (contains beneficial probiotics) 1
• Fresh fruits and vegetables 1
• Frequent small meals rather than large portions 4

Foods to Strictly Avoid:

• High simple sugar foods: Soft drinks, undiluted apple juice, Jell-O, presweetened cereals 1
• High-fat foods (can exacerbate diarrhea) 1
• Hypotonic fluids in patients with severe diarrhea or high-output stomas 3

Special Populations

Infants and Breastfed Children:

Continue breastfeeding on demand throughout the entire diarrheal episode without interruption. 1, 2, 4 This is a critical recommendation from the WHO and AAP that should never be violated. 1

Bottle-Fed Infants:

Immediately reintroduce full-strength, lactose-free or lactose-reduced formulas after rehydration. 1 Most standard enteral formulations are lactose-free because lactose intolerance commonly occurs during critical illness. 5

Patients with High-Output Stomas or Severe Diarrhea:

Monitor fluid output and urine sodium, decrease hypotonic fluid intake, and increase saline solutions (glucose-electrolyte solutions). 3 These patients require 71% treatment with oral hypotonic fluid restriction combined with glucose-saline solution and anti-diarrheal medication. 3 Consider food intolerances that may enhance fluid output. 3

Hydration Takes Priority Over Diet

Oral rehydration solution (ORS) with reduced osmolarity (<250 mmol/L) is the first-line therapy and takes absolute priority over dietary interventions. 1, 2 Administer 50-100 mL/kg over 2-4 hours for mild-to-moderate dehydration. 2 Replace each watery stool with an additional 10 mL/kg of ORS. 1, 2

For severe dehydration (shock, altered mental status, inability to tolerate oral intake), use isotonic IV fluids (lactated Ringer's or normal saline) until stabilized, then transition to ORS. 2, 4

Evidence-Based Adjuncts

Rice-based diets have demonstrated clinical efficacy in persistent diarrhea, with 81% of patients recovering within seven days. 6 A rice-based formulation showed median carbohydrate absorption of 81% even in persistent diarrhea patients. 6

Consider probiotics (Lactobacillus GG or Saccharomyces boulardii) to reduce symptom severity and duration. 1, 2, 4 However, probiotics should not be used for treatment of active Crohn's disease. 3

Critical Pitfalls to Avoid

• Never withhold food—this worsens malnutrition without improving diarrhea 2, 4
• Never use antimotility agents (loperamide) in children <18 years 3, 2, 4
• Never use loperamide in patients with bloody diarrhea, fever, or inflammatory diarrhea due to toxic megacolon risk 3, 2, 4
• Never interrupt breastfeeding in infants with diarrhea 1, 2
• Never give high simple sugar drinks (undiluted juice, soft drinks) as they worsen osmotic diarrhea 1

When Parenteral Support Is Needed

Parenteral infusions (fluid and electrolytes) may be required for ongoing high-output stomas that fail to respond to oral restriction and glucose-saline solutions. 3 In one study, 8% of high-output stoma patients required continued parenteral or subcutaneous saline in the home setting. 3