Brief Answer:
Probably the symptoms are food related or a bleeding ulcer, follow the advice below

Detailed Answer:
Hello dear and welcome to ‘Ask A Doctor’ service. I have reviewed your query and here is my advice.

I understand your concern.

Black stool can be related to the presence of blood.

It comes from the upper part of the gastrointestinal tract, especially stomach from a bleeding ulcer.

It can also be related to certain foods such as licorice.

Iron supplements can also be the cause of black stool.

I suggest you to do a stool test to confirm the diagnosis.

If the presence of blood is confirmed I would recommend an endoscopy to confirm the source of the blood.

Meanwhile, I can recommend using antacid such as Maloox three tablets a day.

I also recommend to use medications to reduce the acidity in the stomach such as Omeprazole 20 mg daily in the morning.

After the examinations recommended you can contact me again for further evaluation.

Hope I have answered your query. Let me know if I can assist you further.

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