Oncologic Emergencies Practice Test

Rasburicase acts quickly to lower uric acid by converting it to allantoin, so you want to check uric acid at a time that reflects this early response. Monitoring 4–8 hours after the dose captures the peak effect and shows whether the uric acid level has fallen as expected, guiding any needed further dosing. Checking immediately after the dose may still show high levels because the drug hasn’t had time to act, while waiting longer (such as 24 hours) risks missing a rebound or ongoing rise in uric acid as the initial clearance phase passes. Thus, the best timing is 4–8 hours after administration.