Black stools is suggestive of an upper GI bleed. I would consider an upper endoscopy to see whether an ulcer has recurred. I agree with the ultrasound and the H Pylori test, however the upper endoscopy needs to be done.
Depending on the cause, treatment options can range from PPI therapy to antibiotics (if H Pylori) is present.
The alternating patterns of constipation and diarrhea can be suggestive of irritable bowel disease. Increasing fiber in the diet would be the first step in treating this.
These options can be discussed with your personal physician.
Followup with your personal physician is essential.
This answer is not intended as and does not substitute for medical advice - the information presented is for patient education only. Please see your personal physician for further evaluation of your individual case.
Kevin, M.D.
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