Introduction: Upper gastrointestinal bleeding (UGIB) is a common medical condition, as well as cause of morbidity and mortality. Peptic ulcer disease is the most common cause of UGIB in the United States. Helicobacter pylori and the use of NSAIDs are the most common identified risk factors. Complications of peptic ulcer disease (PUD) include bleeding, perforation, penetration, and gastric outlet obstruction. For anatomical reasons duodenal ulcers, especially posterior, are more likely to bleed and may erode into the gastroduodenal artery. However, massive UGIB due to cystic artery bleeding is extremely rare and has been reported only in few case reports. Case report: A 60-year-old female patient with a past medical history of history of renal transplant complicated by rejection, end stage renal disease on peritoneal dialysis, and benign essential hypertension presented to our institution with abdominal pain, fever, and was diagnosed with Candida peritonitis. She was admitted and started on Micafungin. Her hospital course was complicated by right upper extremity discoordination. Further evaluation including brain MRI showed acute cerebellar ischemic stroke, so Clopidogrel was initiated in combination with Aspirin that the patient was already using. Two days after initiation of dual antiplatelet therapy, she had two episodes of coffee ground emesis. Her hemoglobin dropped from 10.4 g/dl to 7.9 g/dl. Clopidogrel was held, she was started on pantoprazole continuous infusion. and esophagogastroduodenoscopy was planned. EGD showed a large ulcer in the posterior duodenal bulb with a large adherent blood clot overlying the ulcer. No endoscopic intervention was performed. Over the following night, she became hypotensive and had multiple episodes of melena. She was transferred to the intensive care unit and interventional radiology was consulted. An arteriogram was done that showed massive bleeding from the cystic artery into the duodenum, and it was successfully embolized. Her hemoglobin and vital signs stabilized following the procedure.Figure 1Figure 2Conclusion: We report a rare case of massive UGIB due to cystic artery bleeding. It should be considered in cases of bleeding duodenal ulcers especially if it's anterior or post-bulbar. Angiography and attempting embolization seems to be a reasonable approach. An important consideration when embolizing the cystic artery is the risk of necrotizing cholecystitis and the patient should be watched closely for this complication.