Brief Answer:
Need some more information

Detailed Answer:
Hi dear.Thanks for your query.

Since the stool is black I would ask for stool analysis and test to detect the presence of blood(guaiac test).
I would like to know if you are mentioning about mouth ulcer?If yes, please upload a snap if possible?

However, I would also like to know some more information-
Do you have fever, pain abdomen?
Is it foul smelling?
How much is the output(volume)?
Is there any history of recent travel or change in food (due to party)?
Do you have any other medical or surgical history in your past?

I would suggest to give the stool sample for examination and hold Ofloxacin for a while.Empirical antibiotic therapy can be started before the test reports.I shall suggest once you share the answers for my questions.

Donot take eldoper since eldoper does not treat the cause. It is only symptomatic therapy.

Suggest to have Oral Rehydration Solution(ORS).ORS prevents dehydration and compensates for electrolyte loss.You can take depending on stool output.But I recommend a minimum of 2-3 liters per day.

Await your reply soon.

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Brief Answer:
Visit ER.Needs to be managed at earliest

Detailed Answer:
Thanks for sharing the information.

Blackish stool is suggestive of active bleeding from peptic ulcer.This needs immediate medical supervision.

I would suggest endoscopic evaluation, identify the cause of bleeding and stop the bleeding (prefer injection therapy to coagulate the blood vessel) an thus prevent further bleeding.

Advice nil per oral (donot take anything by mouth).Visit the ER if you are covered under insurance.This needs to be treated at the earliest to prevent further blood loss.

Hope this answers your query. Get well soon.

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