Osmotic diarrhea

What it means

Osmotic diarrhea results from the presence of osmotically active, poorly absorbed solutes in the bowel lumen that inhibit normal water and electrolyte absorption.

Osmotic diarrhea involves an unabsorbed substance that draws water from the plasma into the intestinal lumen along osmotic gradients. Secretory diarrhea results from disordered electrolyte transport and, despite the term, is more commonly caused by decreased absorption rather than net secretion. Inflammatory diseases cause diarrhea with exudative, secretory, or osmotic components.

Rare diseases that can present with this1

The range is how often this sign appears among people diagnosed with each disease — it is not a probability of having any of them. Many of these signs also occur in common, non-rare conditions. A sign on this page is a conversation to have with a clinician, not a conclusion.

Part of the broader category