The confused cancer patient: a case of 5-fluorouracil–induced encephalopathy

The fluorinated pyrimidine 5-fluorouracil (5-fu) is an anticancer agent used in most adjuvant and palliative treatment regimens for colorectal cancer. Neurotoxicities are considered extremely rare side effects of 5-fu. Here, we report a case of 5-fu–induced encephalopathy, manifesting as seizures and delirium, in an era of oxaliplatin-containing chemotherapy. If ammonia levels are elevated, lactulose may be considered in the initial management of neuropsychiatric complications from 5-fu.