Brief Answer: This is treatable. Detailed Answer: Hi. Noted the history of high blood pressure controlled with medicines. Also noted the present history. It is good that the upper GI endoscopy, CT scan is normal. Black tarry stools are indicative of an internal bleeding in the small intestine or initial part of large bowel. Reduced Hemoglobin is one of the important factors of fatigue and light-headedness. In today's practice there is no need to remain anemic. We have to find the reason :: I can suggest you the line of management. Please remember he may need these tests repeatedly as the bleeding spot can be seen only if he is bleeding in the intestine at that particular timing of tests. SO can be tedious. But if we can find the bleeding spot, it can be rectified with good results. *CT or MRI Angiography *Capsule endoscopy *Colonoscopy *Exploratory Laparoscopy or Laparotomy for diagnosis and if the reason is found - definitive treatment at the same time. * Thorough blood testing including bleeding time, clotting time, Platelet count, Prothrombine time, blood iron. *Another good possibility is - if the bleeding point can be visualized at the Angiography and if that center has the facility, the Interventionist can do embolization of the feeding vessel. I am sure your brother will be definitely well treated although this is a bit tricky situation and I repeat sometimes these procedures may need to be repeated as they can detect only if bleeding is active. *Capsule endoscopy has an advantage that it can exactly tell us the nature of lesion inside like angioma, ulcer or otherwise and definitive treatment can be planned then.

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