What is the treatment for diarrhea?

Treatment of Diarrhea

The cornerstone of diarrhea treatment is oral rehydration solution (ORS) for mild to moderate dehydration, with immediate intravenous fluids reserved only for severe dehydration (≥10% fluid deficit) with shock or altered mental status. 1

Initial Assessment

Assess dehydration severity through physical examination:

• Mild dehydration (3-5% fluid deficit): Increased thirst, slightly dry mucous membranes 1, 2
• Moderate dehydration (6-9% fluid deficit): Loss of skin turgor, skin tenting when pinched, dry mucous membranes 1, 2
• Severe dehydration (≥10% fluid deficit): Severe lethargy or altered consciousness, prolonged skin tenting (>2 seconds), cool and poorly perfused extremities, decreased capillary refill 1, 2

Rapid deep breathing, prolonged skin retraction time, and decreased perfusion are more reliable indicators than sunken fontanelle or absence of tears. 1, 2

Treatment Algorithm Based on Dehydration Severity

No Dehydration

• Skip rehydration phase entirely 1
• Begin maintenance therapy immediately with age-appropriate diet 1
• Replace ongoing losses: 10 mL/kg ORS for each watery stool, 2 mL/kg for each vomiting episode 1

Mild Dehydration (3-5% deficit)

• Administer ORS containing 50-90 mEq/L sodium at 50 mL/kg over 2-4 hours 1, 2
• Use teaspoon, syringe, or medicine dropper to give small volumes initially (one teaspoon), gradually increasing as tolerated 1
• Reassess hydration status after 2-4 hours 1, 2
• If rehydrated, progress to maintenance phase; if still dehydrated, reestimate deficit and restart rehydration 1

Moderate Dehydration (6-9% deficit)

• Administer ORS at 100 mL/kg over 2-4 hours using same procedure as mild dehydration 1, 2
• Consider nasogastric administration if patient cannot tolerate oral intake 1
• Reassess after 2-4 hours and adjust accordingly 1

Severe Dehydration (≥10% deficit)

• Medical emergency requiring immediate IV rehydration 1, 2
• Administer 20 mL/kg boluses of Ringer's lactate or normal saline until pulse, perfusion, and mental status normalize 1, 2
• May require two IV lines or alternate access sites (venous cutdown, femoral vein, intraosseous infusion) 1
• Once consciousness returns, transition to ORS for remaining deficit 1, 2

Maintenance Phase and Nutritional Management

Feeding Guidelines

• Resume age-appropriate usual diet during or immediately after rehydration is completed 1, 2
• Breast-fed infants must continue nursing on demand throughout illness 1, 2
• Bottle-fed infants should receive full-strength, lactose-free, or lactose-reduced formulas immediately upon rehydration 1, 2
• Avoid "resting the bowel" through fasting—early feeding promotes intestinal cell renewal 1, 2

Ongoing Loss Replacement

• Administer 1 mL ORS per gram of diarrheal stool if losses can be measured accurately 1
• Alternatively, give 10 mL/kg for each watery stool and 2 mL/kg for each vomiting episode 1

Antimicrobial Therapy Considerations

Empiric antimicrobial therapy is NOT recommended for most patients with acute watery diarrhea without recent international travel. 1

Exceptions where empiric treatment may be considered:

• Immunocompromised patients 1
• Young infants who are ill-appearing 1
• Bloody diarrhea (dysentery) after stool culture collection 1

Avoid antimicrobials in STEC O157 and other STEC producing Shiga toxin 2 due to risk of hemolytic uremic syndrome. 1

Antimotility Agents

Loperamide should NOT be given to children <18 years of age with acute diarrhea due to risks of ileus, lethargy, and death. 1, 3, 4

For immunocompetent adults with acute watery diarrhea:

• Loperamide may be used once adequately hydrated 1
• Initial dose: 4 mg followed by 2 mg every 2-4 hours or after each unformed stool 1
• Maximum daily dose: 16 mg 1
• Avoid in bloody diarrhea, severe dehydration, or when inhibition of peristalsis could cause complications 4

Critical Pitfalls to Avoid

• Never allow thirsty patients to drink large volumes ad libitum—this increases vomiting; instead administer small frequent amounts 1
• Do not use soft drinks for rehydration—high osmolality makes them inappropriate 2
• Stool cultures are NOT needed for routine acute watery diarrhea in immunocompetent patients 1
• Discontinue loperamide immediately if constipation, abdominal distention, or ileus develops 4
• Monitor for toxic megacolon in AIDS patients or those with inflammatory bowel disease 4

When to Switch to IV Therapy

Transition from ORS to IV fluids if:

• Severe dehydration, shock, or altered mental status present 1, 2
• Paralytic ileus develops 1
• Patient cannot tolerate oral/nasogastric intake 1
• ORS therapy fails after adequate trial 2