<prompt> Dose reduction should be done for which of the following anticancer drug, if Allopurinol is usedMethotrexateMitoxantrone6-MercaptopurineMitomycin-C  <response>: Allopurinol inhibits the metabolism of 6-mercaptopurine and result in toxicity. Therefore if Allopurinol is used, dose of 6-mercaptopurine should be decreased by 75. 