Intraductal papillary mucinous neoplasms (IPMNs) of the pancreas are a spectrum of benign to malignant epithelial neoplasms that are characterized by papillary proliferation, duct dilation, and cyst formation. A rare complication of IPMNs is fistula formation into adjacent organs such as the duodenum, biliary system, and stomach. Here, we report a case of IPMN with a pancreaticobiliary fistula and pancreaticogastric fistula. An 84-year-old woman with early Alzheimer’s disease was diagnosed with IPMN of the pancreas. She deferred surgery given her age and remained asymptomatic for five years until presenting with cholangitis. She had been further evaluated and was found to have a pancreaticobiliary fistula, which was treated with biliary stent placement. Her subsequent admission involved the formation of a new pancreaticogastric fistula. This case highlights potential complications of excess mucin production from unresected IPMNs and demonstrates a guarded prognosis in elderly patients.