Treatment of Diarrhea Lasting Longer Than One Week
The cornerstone of treatment for diarrhea lasting longer than one week is oral rehydration therapy with reduced osmolarity oral rehydration solution (ORS), while specific antimicrobial therapy should be reserved for cases with identified pathogens or specific risk factors. 1
Initial Assessment and Rehydration
Rehydration Therapy
- First-line treatment is reduced osmolarity ORS with composition of 75-90 mEq/L sodium, 20 mEq/L potassium, 65-80 mEq/L chloride, 10 mEq/L citrate, and 75-111 mmol/L glucose 1
- For adults with mild-to-moderate dehydration, use commercially available oral solutions containing 45-75 mEq/L of sodium 2
- For severe dehydration, begin with intravenous fluids (60-100 ml/kg of 0.9% saline) over 2-4 hours to restore circulation, then transition to ORS 1, 2
Warning Signs Requiring Medical Attention
- Seek medical attention if:
- Hospitalization is indicated for severe dehydration, persistent vomiting, toxic appearance, signs of sepsis, or immunocompromised status 1
Dietary Management
- Resume age-appropriate usual diet during or immediately after rehydration 3
- Small, light meals are recommended based on appetite 3
- Avoid fatty, heavy, spicy foods, caffeine, and stimulants 3
- Consider temporary lactose restriction, especially for prolonged episodes 3, 1
- For adults, the BRAT diet (bananas, rice, applesauce, toast) may be helpful 1
- Continue breastfeeding throughout the entire illness in infants 1
Pharmacological Interventions
Antimotility Agents
- For adults with non-bloody diarrhea, loperamide can be used (starting with 4 mg followed by 2 mg after each loose stool, maximum 16 mg/day) 3, 1
- Antimotility drugs should not be given to children under 18 years of age with acute diarrhea 3
- Avoid antimotility agents in cases of dysentery (bloody diarrhea) or fever 3, 1
Antiemetics
- Ondansetron may be given to facilitate oral rehydration in children >4 years and adolescents with vomiting 3
Antimicrobial Therapy
- Empiric antibiotics are generally not recommended for most cases of acute watery diarrhea without specific risk factors 1
- Consider antimicrobial therapy for:
- Persistent diarrhea with identified bacterial pathogen
- Clostridium difficile infection (vancomycin 125 mg orally four times daily for 10 days) 4
- Recent international travel with moderate to severe symptoms (azithromycin or ciprofloxacin based on local resistance patterns) 1
- Immunocompromised patients 1, 5
Probiotics
- May be considered to shorten the duration of illness, though evidence for their use in early treatment is limited 3, 6
Special Considerations for Persistent Diarrhea (>1 week)
- Evaluate for non-infectious causes including medication side effects, inflammatory bowel disease, irritable bowel syndrome, or malabsorption disorders 1, 7
- Consider stool testing for:
- For C. difficile-associated diarrhea, vancomycin has shown clinical success rates of approximately 81% 4
Prevention of Complications and Spread
- Maintain adequate fluid intake as indicated by thirst 3
- Practice proper hand hygiene after toilet use and before food preparation 1
- Avoid preparing food for others while symptomatic 1
- Monitor for signs of dehydration (decreased urine output, dry mucous membranes, decreased skin turgor, tachycardia) 1, 5
Common Pitfalls to Avoid
- Overuse of antibiotics in likely viral cases
- Inadequate fluid replacement
- Premature use of antimotility agents in dysentery
- Ignoring warning signs requiring medical attention
- Failing to consider local antibiotic resistance patterns 1
- Treating without identifying the cause of chronic diarrhea
- Overlooking medication-induced diarrhea 1
Diarrhea lasting longer than one week warrants a more thorough evaluation than acute self-limited episodes, as persistent symptoms may indicate a more serious underlying condition requiring specific treatment beyond supportive care.