Generalized sensorimotor dysfunction may become progressively more severe with continued treatment. Although most effects usually disappear by 6 wk after discontinuation, some neuromuscular difficulties may persist for prolonged periods. In presence of leukopenia or a complicating infection, carefully consider whether next dose should be given. A fall in WBC or platelet count may occur, particularly when previous therapy or disease itself has reduced bone marrow function. Thrombocytopenia, if present upon initiation, may actually improve before appearance of marrow remission.
Improvement occurs in hyponatremia and renal loss of sodium with fluid deprivation.
Onset of reactions may occur minutes to several hours after injection and may occur up to 2 wk after a mitomycin dose. Progressive dyspnea requiring chronic therapy may occur. Do not readminister vincristine. If extravasation occurs, discontinue injection immediately and introduce remaining portion of dose into another vein. Local injection of hyaluronidase and application of moderate heat to area of leakage will help disperse drug and may minimize discomfort and possibility of cellulitis.