While sitting on the john for the fourth time yesterday evening, the thought entered my head: What causes diarrhea? I know some general information (Large intestine usually should absorb water, but for some reason fails to), but was hoping someone would give me dirty details. Thanks.
Posted Dec 17, 2011, 9:42 PM UTC
I started writing a thing, but this website explains it really nicely:
http://www.vivo.colostate.edu/hbooks/pathphys/digestion/smallgut/diarrhea.html
It's all about the movement of osmotically active particles and the alterations in this movement. Water follows by osmosis.
It can also happen with certain infections when your body tries to force as much water back through your intestinal lining and speed up your peristaltic contractions (which hurts like shit, I might add) to flush it out as fast as possible.
That's why something like norovirus gives you high-pressure, crampy, liquid shits for so long.
If you want some general information why don't you just read the wiki article on it?
Some bacteria ( like C.diff) produce enterotoxins, which cause havoc with the cellular machinery of the epithelial layer in the gut. The end result being much more water being pumped out into the lumen of the intestine, causing looser stools.
The cramps and explosive events are also caused by spasms in your intestine, as a response to infection, the desired result being flushing all the bacteria out of your gut. For the bacteria, it can be beneficial because they get to leave the body and find another host.