What is the treatment for diarrhea?

Treatment of Diarrhea

The cornerstone of diarrhea management is oral rehydration solution (ORS) for all cases of mild to moderate dehydration, with immediate dietary resumption after rehydration and antimicrobial therapy reserved only for specific bacterial pathogens or high-risk patients. 1, 2, 3

Immediate Assessment of Dehydration Severity

Assess dehydration by examining skin turgor, mucous membranes, mental status, pulse, capillary refill, and urine output 2:

• Mild dehydration (3-5% fluid deficit): Increased thirst, slightly dry mucous membranes 1
• Moderate dehydration (6-9% fluid deficit): Loss of skin turgor, skin tenting, dry mucous membranes 1
• Severe dehydration (≥10% fluid deficit): Severe lethargy, prolonged skin tenting, decreased capillary refill 1

Rehydration Protocol

Mild to Moderate Dehydration

• Administer 50 mL/kg of ORS (containing 50-90 mEq/L sodium) over 2-4 hours for mild dehydration 1, 2
• Administer 100 mL/kg of ORS over 2-4 hours for moderate dehydration 1, 2
• Use reduced osmolarity ORS (<250 mmol/L) as first-line therapy 3
• For intractable vomiting, give small volumes (5 mL) every 1-2 minutes with gradual increases, or consider nasogastric ORS infusion 2, 3

Severe Dehydration

• Immediate IV rehydration with 20 mL/kg boluses of Ringer's lactate or normal saline 1
• IV fluids are also indicated for shock or altered mental status 3

Replacement of Ongoing Losses

Replace ongoing stool and vomit losses continuously during both rehydration and maintenance phases: 2

• 10 mL/kg ORS for each watery/loose stool 2
• 2 mL/kg ORS for each vomiting episode 2

Nutritional Management

Infants and Children

• Continue breastfeeding on demand throughout the diarrheal episode 1, 2, 3
• Resume age-appropriate usual diet immediately after rehydration is completed 1, 2
• Administer full-strength, lactose-free or lactose-reduced formulas to bottle-fed infants immediately upon rehydration 1, 2
• Consider oral zinc supplementation (20 mg daily for 10-14 days) in children 6 months to 5 years in areas with high zinc deficiency or malnutrition 3

Adults

• Resume food intake guided by appetite, avoiding fatty, heavy, spicy foods, caffeine, and lactose-containing foods in prolonged episodes 2

Antimicrobial Therapy

Antibiotics are NOT recommended for most acute watery diarrhea without recent international travel 1, 3:

When to Use Antibiotics

• Shigella infection 1
• Suspected cholera 1
• Enteric fever (typhoid) 1
• Immunocompromised patients 3
• Ill-appearing young infants 3

Critical Contraindication

• NEVER give antibiotics for STEC O157 or any STEC producing Shiga toxin 2, as they increase the risk of hemolytic uremic syndrome 1, 3

Adjunctive Pharmacologic Therapy

Loperamide

• May be given to immunocompetent adults with acute watery diarrhea (2 mg per dose) 3, 4
• Absolute contraindications: 3, 4
  • Children <18 years of age (contraindicated <2 years due to respiratory depression and cardiac risks) 1, 4
  • Bloody diarrhea 3
  • High fever 3
  • Suspected inflammatory diarrhea 3
• Avoid higher than recommended doses due to risk of cardiac arrhythmias, QT prolongation, and sudden death 4

Antiemetics

• Ondansetron may be given to children >4 years and adolescents with vomiting to facilitate oral rehydration tolerance 3
• Use only after adequate hydration is initiated 3

Probiotics

• May be offered to reduce symptom severity and duration in immunocompetent patients with infectious or antimicrobial-associated diarrhea 3

Critical Pitfalls to Avoid

• Do NOT use "clear liquids" (sports drinks, juices, sodas) instead of ORS—they have inappropriate electrolyte composition and cause osmotic diarrhea 1, 2, 3
• Do NOT withhold food—early refeeding prevents nutritional consequences and promotes intestinal recovery 1, 3
• Do NOT use antimotility agents as substitute for fluid and electrolyte therapy—they are ancillary only after adequate hydration 3
• Do NOT give antibiotics for vomiting alone—use small frequent volumes of ORS with close supervision 1
• Do NOT treat asymptomatic contacts—advise infection control measures instead 3

When to Seek Specialist Referral

Most cases of acute diarrhea do not require laboratory workup or stool cultures 3. Reserve diagnostic investigation and specialist referral for 3, 5:

• Severe dehydration or illness
• Persistent fever
• Bloody or mucoid stools
• Immunosuppression
• Suspected nosocomial infection
• Red flag symptoms (weight loss, anemia, palpable abdominal mass)

Special Populations

• Elderly patients require medical supervision rather than self-medication due to higher risk of rapid dehydration, electrolyte imbalances, renal decline, and malnutrition 2
• Pediatric patients <6 years have greater variability of response to treatment, and dehydration further influences this variability 4