Get your health question answered instantly from our pool of 18000+ doctors from over 80 specialties
124 Doctors Online

By proceeding, I accept the Terms and Conditions

Dr. Andrew Rynne
Dr. Andrew Rynne

Family Physician

Exp 50 years

HCM Blog Instant Access to Doctors
HCM BlogQuestions Answered
HCM Blog Satisfaction

What causes black stool?

Answered by
Dr. Michelle Gibson James

General & Family Physician

Practicing since :2001

Answered : 16699 Questions

Posted on Tue, 7 Jun 2016 in Digestion and Bowels
Question: My feces have become black in color whereas they were previously medium brown; I had a colonoscopy about 18 months ago and it was clear.
Answered by Dr. Michelle Gibson James 1 hour later
Brief Answer:
may be due to iron, bismuth meds, or bleeding from upper gi tract

Detailed Answer:
HI, thanks for using healthcare magic

The colonoscopy done 18 months ago would rule out more serious causes such as cancer of the colon

Other causes of black stool include: (a)use of iron supplements or meds such as pepto bismol which have in bismuth
(b)bleeding from the upper gastrointestinal tract such as the esophagus, stomach or small intestines eg from gastritis, ulcers of the stomach or esophagus, abnormal blood vessels

Because there is a risk that it can be associated with bleeding, it may be best if you see your doctor for assessment if it continues.

Your doctor would examine your abdomen and may also suggest blood tests such as a complete blood count to check your hemoglobin level.

Depending on the results of the examination, a look of the upper gastrointestinal tract may be needed.

I hope this helps, feel free to ask any other questions
Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar

The User accepted the expert's answer

Share on
Question is related to
Diseases and Conditions
Medical Procedures
Lab Tests

Recent questions on  Black stool

doctor1 MD

I am having black specks in faeces, they are not visible at a glance, but when I take faeces in hand and then rub it , it can be seen ,no other...

doctor1 MD

Hello, Is black stool something to worry about, even though I recently had a CT (with barium) that noted a normal stomach, small bowel, and small...

doctor1 MD

I have black, gassy stool.

doctor1 MD

I am feeling pain in my anal line during bowel movement . stool is blackish. when it was started first time (2 months ago) a little bit of bleeding...

doctor1 MD

My wife just had a baby girl on the ninth. She has been experiencing sharp lower abdomen pains when drinking fluids, and at times when she doesn t...

doctor1 MD

Hi on Oct 12 I had heavy bleeding and cramping I was 8weeks 6 days pregnant. The Dr said the plasenta was detaching from my uterus and was having a...

doctor1 MD

Hello my dad is 64 years old and was just dx with liver cancer . He has ascites and edema in his right leg. He won t eat anything except for tea...