Chronic constipation and faecal impaction are common in the elderly, particularly in institutionalized patients and those with neurological impairment. Faecaloma formation is an extreme manifestation of coprostasis that can lead to stercoral ulcerations and perforation, a recognized severe complication. We present the case of an uncommon life-threatening complication resulting from a giant rectal faecaloma, which has rarely been reported in the literature. The patient presented with haemodynamic shock from profuse per-rectum haemorrhage. Clinical examination revealed a hard central abdominal mass and triple-phase CT of the abdomen demonstrated a tumour-like mass of hard stool in the rectum measuring up to 25 cm and stretching the adjacent vasculature, causing intraluminal active arterial haemorrhage. Emergency selective arterial embolization performed by the interventional radiologists successfully controlled the bleeding with a good outcome. This case highlights a rare but possibly fatal complication of chronic constipation and emphasizes the importance of having access to an acute interventional radiology service capable of promptly dealingwith life-threatening presentations.