Severe hemorrhagic cystitis associated with oral cyclophosphamide (CYP) therapy has rarely been reported in the past 20 years, probably because this condition has largely disappeared because of the use of shorter courses of CYP, either oral or IV. Herein, we describe a patient who received 309 g of oral CYP over a 4-year period to treat Wegener's granulomatosis (WG) that initially involved brain, lung, and kidney. She came under our care for the first time when she presented with a one-day history of oliguria and passing blood clots. Severe hemorrhagic cystitis was present. It eventually required cystectomy. Despite her massive CYP exposure her kidney biopsy showed acute crescentic glomerulonephritis. She survived her acute illness only to die 2 months later of acute leukemia. This patient is a reminder that severe hemorrhagic cystitis from oral CYP still exists, and that WG can be resistant to even toxic doses of oral CYP. Alternative therapies are discussed.