Dear friend, welcome and thanks for entrusting your query here at Healthcaremagic!
I am Dr. Prasad Akole (Critical Care Expert- http://bit.ly/Dr-Prasad-Akole) and am glad to address to your query here.
You seem to have gut bleeding. (gastro-intestinal hemorrhage). Black stools (malaena) is due to altered blood in stools.
It is highly likely that you have an ulceration somewhere in the stomach or the lower bowel.
You need urgent evaluation, hemogram, urea,
creatinine,
sonography, upper and lower GI
endoscopy. If appropriate, a CT scan of abdomen/ pelvis may be asked for.
I would advise an evaluation by a gastro-enterologist and treatment for bleeding.
Possibilities are
ulcerative colitis, IBS (irritable bowel disease),
diverticulosis, cancer, tumour etc.
I hope to have answered your query satisfactorily. I would be glad to answer any further queries. Please ask for any clarifications before closing and rating this query.
Take care and please keep me informed of your progress at http://bit.ly/Dr-Prasad-Akole
Good Luck! Thank you!!