IV bolus 20% given on 3 occasions over 15-30 min at 4-hrly intervals. Patient at high risk of urotoxicity Increase dose to 40% given 4 times at 3-hrly intervals. IV infusion 20% by IV inj followed by 100% of total dose by IV infusion over 24 hr, then followed by 60% by infusion over 12 hr. The final 12-hr infusion may be replaced by 3 inj each of 20% dose at 4-hrly intervals.