Management of Diarrhea

Oral Rehydration and Fluid Management

Oral rehydration is the cornerstone of management for patients with loose stools, using glucose-saline solutions with sodium concentration of at least 90 mmol/L, similar to the World Health Organization formula, and patients should sip these solutions throughout the day rather than drinking large volumes at once 1, 2
The World Health Organization recommends avoiding hypotonic drinks, such as tea, coffee, and juices, and hypertonic solutions, as they can worsen sodium and water loss 1, 2
Monitoring for signs of dehydration, including decreased urine output, concentrated urine, dizziness, and dry mucous membranes, is crucial, and checking urinary sodium concentration, which should be greater than 20 mmol/L, can help detect dehydration 1
The European Society for Clinical Nutrition and Metabolism recommends aiming for 2-2.5 liters of fluids per day, more during hot weather or exercise, and using isotonic drinks rather than hypotonic or hypertonic beverages 3
Patients should use glucose-electrolyte oral rehydration solutions rather than plain water for hydration, as advised by the World Health Organization and the American Gastroenterological Association 2, 4

Loperamide is the preferred antimotility agent, with an initial dose of 4 mg, maintenance dose of 2 mg after each loose stool, and a maximum daily dose of 16 mg, according to the European Society of Gastrointestinal Endoscopy 2
The American Gastroenterological Association recommends loperamide over opiates like codeine phosphate because it is not sedative, not addictive, and does not cause fat malabsorption 2
Loperamide works by slowing intestinal motility, affecting water and electrolyte movement through the bowel, binding to opiate receptors in the gut wall, inhibiting acetylcholine and prostaglandin release, reducing propulsive peristalsis, and increasing intestinal transit time 5
Patients should be monitored for improvement in stool frequency and consistency, and assessed for potential side effects such as abdominal distention, constipation, nausea, or vomiting, and the medication should be discontinued if no improvement is seen after 48 hours 2
Other medications for diarrhea management include:
Contraindications for diphenoxylate with atropine include high fever, bloody stools, infectious diarrhea, and severe dehydration, and risk factors include enhanced CNS depression when combined with alcohol or other CNS depressants, abuse potential at high doses, and masking symptoms of more serious conditions 7

For patients with jejunostomy or high-output stomas, adding extra salt to meals, consuming potassium-rich foods, and eating foods that can thicken output, such as bananas, pasta, and rice, can help manage diarrhea, as recommended by the European Society for Clinical Nutrition and Metabolism 3
The American College of Gastroenterology recommends restricting hypotonic fluids and using glucose-saline supplements if less than 200 cm of jejunum remains 2
Dietary modifications, such as increasing soluble fiber intake, may be beneficial in managing post-surgical bowel dysfunction if the colon is in continuity, and pelvic floor exercises may be considered if sphincter weakness is contributing to symptoms 8

If diarrhea is accompanied by fever, vomiting, or signs of dehydration, the American Society of Clinical Oncology recommends considering hospitalization for IV fluids and closer monitoring, evaluating for infectious causes with stool studies, and considering antibiotics if infection is suspected 9
The British Society of Gastroenterology recommends loperamide for managing diarrhea in post-surgical patients, including those with bowel resections, as it may be given safely before the results of microbiology tests to exclude infection are available 5
The American Academy of Pediatrics recommends avoiding antimotility drugs in children under 18 years of age with acute diarrhea, and in cases of suspected infectious diarrhea with fever or bloody stools 10
Barrier devices may be considered for persistent incontinence 11
For refractory cases, consideration for referral for evaluation for octreotide or tincture of opium is recommended 6
Cardiac adverse events are rare but possible at recommended doses, and loperamide should be used with caution in patients taking medications that prolong QT interval, and ensure adequate hydration as fluid and electrolyte depletion often occur with diarrhea 2