Potentiation of vincristine toxicity by itraconazole in children with lymphoid malignancies

Eight consecutive paediatric patients with acute lymphoblastic leukaemia (ALL) (n = 7) and T-cell non-Hodgkin's lymphoma (NHL) (n = 1) presenting within a 5-wk interval were started on a standard induction protocol which included weekly treatment with vincristine for 4 wk. Itraconazole was commenced as antifungal prophylaxis, 1-21 d after the first injection of vincristine. Within 2 to 4 wk, enhanced vincristine neurotoxicity was noted in all patients, abdominal cramps and constipation occurred most frequently, and one patient developed a bowel perforation associated with paralytic ileus. Hyponatraemia associated with SIADH was observed in three patients and four patients developed seizures. An additional patient with B cell NHL developed seizures 5 d after an injection of vincristine. Recovery was complete in all patients and ranged from 2 d to 15 wk. Conclusion: The extent and consistency of adverse effects documented in this study support the recommendation that concurrent administration of vincristine and itraconazole should be avoided.