Angioedema is self-limited, localized subcutaneous or submucosal swelling that can affect areas with loose connective tissue. Angiotensin converting enzyme inhibitor (ACEi) induced angioedema typically affects the face, lips, mouth and throat. ACEi induced angioedema isolated to the small bowel has been reported in previous case reports. To our knowledge, no prior reports have illustrated ACEi induced angioedema isolated to the colon. We present an atypical presentation of acquired angioedema in an 87 year old Caucasian female who presented with complaints of lower abdominal pain and bright red blood per rectum for one day. She had been having symptoms of diarrhea and lower abdominal pain intermittently for three months. Ischemic and infectious workups were negative. Sigmoidoscopy with biopsies showed a generalized edematous colon and internal hemorrhoids. Mucosal biopsies showed only generalized edema with no evidence of infiltration or malignancy. Hematochezia was attributed to internal hemorrhoids. When lisinopril and losartan were discontinued, her symptoms quickly resolved. After six months the patient continued to be symptom free. Although acquired angioedema of the small bowel is an established complication, it is under-diagnosed. ACEi-induced angioedema of the large bowel has been listed as a complication in the literature, but to our knowledge never formally reported. The diagnosis is primarily clinical as there is no test available to confirm the diagnosis. This case report serves to highlight this rare complication with hopes of limiting morbidity and mortality from complications due to unnecessary invasive procedures.Figure 1Figure 2Figure 3