What is the treatment for a patient with diarrhea lasting one week?

Treatment for Diarrhea Lasting One Week

For an adult with diarrhea persisting for one week, initiate oral rehydration with glucose-electrolyte solutions, continue normal food intake guided by appetite, and start loperamide 4 mg initially followed by 2 mg after each loose stool (maximum 16 mg daily), while assessing for warning signs that require immediate medical evaluation. 1, 2

Initial Assessment

Evaluate for warning signs that necessitate urgent medical attention rather than continued self-management 1, 2:

• High fever (>38.5°C) with bloody stools (dysentery)
• Severe vomiting leading to rapid dehydration
• Clinical signs of dehydration (prolonged skin tenting, decreased capillary refill, altered mental status)
• Worsening symptoms or no improvement after 48 hours of treatment

If any warning signs are present, discontinue self-treatment and seek immediate medical care. 1, 3

Hydration Management

For Adults Without Severe Dehydration

Maintain adequate fluid intake guided by thirst using glucose-containing drinks (lemonades, fruit juices) or electrolyte-rich soups. 1 While oral rehydration solutions (ORS) are essential for children, they are not mandatory for otherwise healthy adults with persistent diarrhea, though they remain an effective option. 1

For Patients With Clinical Dehydration

Administer ORS containing 50-90 mEq/L of sodium 2:

• For mild dehydration (3-5% fluid deficit): 50 mL/kg over 2-4 hours 1
• For moderate dehydration (6-9% fluid deficit): 100 mL/kg over 2-4 hours 1
• Replace ongoing losses with 10 mL/kg for each watery stool 2

For severe dehydration (≥10% fluid deficit, shock), immediate intravenous rehydration with Ringer's lactate or normal saline is required (20 mL/kg boluses). 1

Dietary Recommendations

Resume normal, age-appropriate diet immediately—do not withhold food. 1 Specific guidance includes:

• Consume small, light meals guided by appetite 1
• Avoid fatty, heavy, spicy foods and caffeine-containing beverages (including colas) 1
• Consider avoiding lactose-containing foods (milk) if diarrhea persists beyond one week 1
• The BRAT diet has limited supporting evidence but may be considered 1

Pharmacological Treatment

Antidiarrheal Therapy

Loperamide is the drug of choice for adults with persistent watery diarrhea: 1, 2

• Initial dose: 4 mg
• Maintenance: 2 mg every 2-4 hours or after each unformed stool
• Maximum: 16 mg daily

Important contraindications for loperamide: 1

• Do NOT use in children <18 years
• Avoid if fever and bloody stools are present (risk of toxic megacolon)
• Discontinue if symptoms worsen

Antibiotic Considerations

Empiric antibiotics are NOT routinely recommended for persistent diarrhea at one week unless specific indications exist: 2, 4

• Dysentery (fever with bloody stools): Consider azithromycin or fluoroquinolones
• Recent international travel with febrile illness
• Immunocompromised status

Rifaximin (200 mg three times daily for 3 days) is FDA-approved for travelers' diarrhea caused by noninvasive E. coli but should be discontinued if diarrhea persists beyond 24-48 hours. 3

When to Seek Medical Attention

Patients must seek medical evaluation if: 1, 2

• No improvement within 48 hours of initiating treatment
• Symptoms worsen or overall condition deteriorates
• Development of fever, bloody stools, severe vomiting, or signs of dehydration
• Abdominal distension develops

Special Populations

Children

• Continue breastfeeding throughout the illness 1
• Use lactose-free or lactose-reduced formulas for bottle-fed infants 1
• Replace each watery stool with 10 mL/kg of ORS 2
• Do NOT use loperamide in children <18 years 1

Immunocompromised Patients

Consider earlier antimicrobial therapy and more aggressive management, as these patients are at higher risk for complications. 2

Common Pitfalls to Avoid

• Do not withhold food for 24 hours—early refeeding improves outcomes 1
• Do not use antimotility agents when fever or bloody stools are present—this increases risk of toxic megacolon 1
• Do not assume all persistent diarrhea requires antibiotics—most cases are self-limiting and viral 1, 5
• Do not ignore warning signs—persistent symptoms beyond one week warrant medical evaluation to rule out chronic conditions 2, 5