This came up from when my dog had to go the vet, but I think I read that it applies to humans as well.
This is my understanding: if it’s light-color blood, it is from surface blood vessels, ie in itself a not so immediately serious symptom, and indicates some sort of capillary, hemorrhoid, and/or near to the anus blood-vessel break. Those three are either independent or combined.
If the blood is dark, I was told–by the vet for dogs–the bleeding is starting higher up from the colon directly.
is this more or less correct for people too?
what is the reason for two different type colors of blood? I know that venous blood looks different–but does it macroscopically?–due to relative lack of oxygenation (but would love to be corrected and learn more).
If the blood comes from far enough up the digestive tract that it gets partially digested, you get black or tarry stools. The black color comes from the iron in the blood. Iron supplements can also cause black stools. This is true for people too.
For humans, it also means a colonoscopy in your future. And THAT, Dear Friends, is why many people set it aside and think, “Maybe it’s nothing, maybe it will go away.”
Colonoscopy = no fun
Getting dead from colon cancer = even less fun
~VOW
Colonsocopy actually = some serious drug-induced short term diahrhea, followed by a non-event at the Dr’s office followed by a lazy day sleeping off the meds.
It’s not anything anybody ought to dread. It’s a bit more hassle than a teeth cleaning, which itself is only slightly more hassle than a haircut.
Same thing - just that the blood is trickling down so slowly it becomes a vein within the stool instead of covering it.
If there is no stool, just blood coming from your anus, see a doc.