The doctor eases an endoscope, a thin tube containing a tiny camera, through your mouth (or occasionally nose) and down into your stomach to look at the stomach lining. The doctor will check for inflammation and may remove a tiny sample of tissue for tests. This procedure to remove a tissue sample is called a biopsy.
Blood test.
The doctor may check your red blood cell count to see whether you have anemia, which means that you do not have enough red blood cells. Anemia can be caused by bleeding from the stomach.
Stool test.
This test checks for the presence of blood in your stool, a sign of bleeding.

