Postoperative gastrointestinal (GI) and hepatic complications are common, significantly contributing to increased morbidity, prolonged hospital stay, and higher perioperative mortality. GI complications include ileus, GI bleeding, anastomotic leaks, and mesenteric ischemia. Hepatic complications encompass postoperative jaundice, ischemic hepatitis, sepsis-associated cholestasis, and drug-induced liver injury. A historically important condition is halothane hepatitis, once a feared complication of anesthesia, now exceedingly rare. The pathogenesis of hepatic complications is multifactorial, including hypoperfusion, hypoxemia, transfusion reactions, infection, and drug-induced injury. While halothane has been withdrawn from routine use in the USA, occasional reports of hepatotoxicity with modern volatile anesthetics such as isoflurane, sevoflurane, and desflurane suggest that immune-mediated hepatic injury remains possible, albeit extremely rare and far less common than with halothane. Recognition of GI and hepatic complications requires a systematic approach integrating clinical signs, laboratory evaluation, and imaging. Management strategies focus on prevention, supportive care, correction of underlying pathophysiologic insults, and avoidance of hepatotoxic exposures. A working knowledge of these complications allows for timely diagnosis, effective intervention, and coordination with surgical and hepatology colleagues to optimize outcomes.