Hi
Black stool can mean blood. It can also be the result of taking iron or foods high in iron.
I'm glad you are having the colonoscopy. It will rule out if there is serious trouble.
You might want to let the doctor know today about the black stools though.
If you start having weakness, or stomach pain, or start vomitting anything that looks like coffee grounds, you will want to get to an ER as soon as you can.
Hope that helps,
Kerry
Kerry, RN
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