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Dr. Andrew Rynne
Dr. Andrew Rynne

Family Physician

Exp 50 years

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What causes blood in stool?

Answered by
Dr. Pravin Gore


Practicing since :1995

Answered : 82 Questions

Posted on Thu, 11 Dec 2014 in Colon Cancer
Question: Hi dr,
I have blood in stool a week ago(looked like hard stool) for the next 2 days I saw change in bowl habits (had 2 bowl movements normal would be one), next day I had very liquidy movement, then the next day I had greenish movement, next day was normal and today I had black spots (blotchy) and brown solid movement. It was not tarry and no foul smell to it. I did start prenatal vitamins on friday night and had a normal movement yeaterday but today it was blotchy brown and black.Do you think it's something serious like cancer?
Answered by Dr. Pravin Gore 56 minutes later
Brief Answer:
Get colonoscopy done

Detailed Answer:
first let me tell you ' Rare diagnosis are rarely correct'
cancer possibility arises if there is a family history of some blood relative already has cancer. Do you have family history?
still change in bowel habit is an indication. I would suggest you get a Colonoscopy done from a gastroenterologist.
take care.
wish you good health
Above answer was peer-reviewed by : Dr. Bhagyalaxmi Nalaparaju
Follow up: Dr. Pravin Gore 11 minutes later
Hi dr,
I will but does it sound serious? The black stool does not look tarry or has bad smell to it. Also I did take prenatal vitamin with 150% iron which is 27 mg of iron. I know we can not diagnose just with symptoms and online. But does it sound serious? I have absolutely no other symptoms. No family history of cancer either. From your previous experience does it sound like cancer?

Thank you
Answered by Dr. Pravin Gore 21 minutes later
Brief Answer:
It seems nothing serious

Detailed Answer:
an iron supplement can make your stools blackish. For all practical purposes, yours seem to be an iron intake related change in bowel colour, consistency as well as frequency. Other possibility is a colonic infection called colitis (Can be rule out by stool test and culture)
I would still recommend a Colonoscooy just to be safe and sure that there is nothing to worry about (especially Cancer).
Take care.
wish you good health
Above answer was peer-reviewed by : Dr. Bhagyalaxmi Nalaparaju
Follow up: Dr. Pravin Gore 12 minutes later
Hi doctor,
Thank you for the response. Iron was just added 2 days ago after which I saw black bowel moment. General habits were changed before that. Like 3-4 days. All of this happened in just 1 week period. I'm not sure if anything related to cancer would happen so quick all at once one after another. From your experience do you think it will happen so fast in case of cancer?
In case of colorectal cancer would there be incidence of bright red blood and also black stool? I know bright red is always from rectum area and black is up in the stomach/small intestine.
Thank you so much in advance
Answered by Dr. Pravin Gore 32 minutes later
Brief Answer:
cancer colonoscopy

Detailed Answer:
chill dear. Please donot panic.
Colon cancer doubling time is approximately 18 months.
It is not going to grow overnight to give symptoms.
take a colonoscopy test asap to clear the 'pathology in your mind'
Relax. Even if unfortunately there is a cancer, it is curable if diagnosed in early stage.
So please see a gastroenterologist and get colonoscopy done. I do colonoscopy at XXXXXXX specialty hospital, XXXXXXX XXXXXXX

Above answer was peer-reviewed by : Dr. Prasad

The User accepted the expert's answer

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