[4][5] The upper GI tract is defined as the organs involved in digestion above the ligament of Treitz and comprises the esophagus, stomach, and duodenum.

[11] The development of blood in a person's stool results from a variety of conditions, which can be divided into major categories of disease.

These broad categories include cancerous processes or abnormal structure of bowel wall, inflammatory disease, colitis caused by infection or medications and vascular compromise.

Melena is defined as dark, tarry stools, often black in color due to partial digestion of the red blood cells.

[6] Hematochezia is typically presumed to come from the lower portion of the GI tract, and the initial steps of diagnosis include a DRE with FOBT, which if positive, will lead to a colonoscopy.

[48][49] The anoscopy is another type of examination, which can be used along with a colonoscopy, which exams the rectum and distal portion of the descending colon.

[53] Similarly, stomach cancer is treated depending on the staging, although typically requires surgical and medical therapy.

[54] The treatment for motility issues, namely constipation, is typically to improve the movement of waste through the GI tract.

Improving a person's gut motility can reduce the straining during defecation and decrease the risk of developing anal fissures.

[56] Treatment includes topical nitrates or calcium channel blockers and surgical interventions for chronic or complex cases.

[56] Similar to anal fissures, internal hemorrhoids can cause blood on the tissue when wiping, and be felt at the opening of the anus.

Peptic ulcer disease alone can be divided into multiple causes, but is generally initially controlled primarily with a proton pump inhibitor, with the addition of an H2 blocker, or in serious cases, requiring surgical intervention.