gi-hepatology
Stool Osmotic Gap
Differentiates osmotic from secretory diarrhoea. Osmotic gap >125 mOsm/kg suggests osmotic diarrhoea (stops with fasting). Gap <50 mOsm/kg suggests secretory diarrhoea (continues with fasting).
References
- Eherer AJ, Fordtran JS. Fecal osmotic gap and pH in experimental diarrhea of various causes. Gastroenterology. 1992;103(2):545–551.
Related
Curated clinical cross-links plus same-class fallbacks.
Calculators
Drugs
- Mannitol · Osmotic diuretic
- Macrogol (Polyethylene Glycol) · Osmotic Laxative
- Lactulose · Osmotic laxative / Ammonia reduction (hepatic encephalopathy)
- Lactulose (Hepatic Encephalopathy) · Osmotic Laxative / Ammonia-Reducing Agent
- Macrogol (Polyethylene Glycol) · Osmotic Laxative
- Sodium Acid Phosphate Enema · Osmotic / Stimulant Rectal Laxative
Decision support only — verify against MDCalc, NICE, or your local guideline before clinical use.