Brief Answer:
Colonoscopy to be done.

Detailed Answer:
Hello,
Thanks for query.
There are a few things to consider when a person says he has black stool.
The first thing is if it is blood. Bleeding in upper gastrointestinal tract gives black tarry color to stools.A stool microscopy that will confirm the presence of blood with the stools. Generally, blood coming from higher levels (stomach and small bowel) converts into a dark coal black colour due to the changes the blood has in the bowel.Have you ever had a colonoscopy done? After the age of 50, it is recommended that all people should have a colonoscopy every 5-10 years. Even if you have had this test in the last 5 years it might be recommended to repeat it as you are having this bleeding if the stool tests confirm you are really bleeding.

For gas i would suggest you to take a probiotic twice daily. Probiotcs help to replete good bacterias in gut.When these good bacterias are destroyed food is acted upon by bad bacterias causing fermentation of food leading to production of large amount of gas.
Secondly over the counter medication like omeprazole can be taken for relief.

I hope this is helpful and answers your questions but please feel free to reply in case any more clarification is needed on this.

Kind regards,

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