Rasburicase

How it works

It catalyses the oxidation of uric acid to allantoin, a more soluble compound that is more readily excreted, rapidly lowering plasma urate.

Prescribing in practice

• Rasburicase is contraindicated in glucose-6-phosphate dehydrogenase deficiency because it can precipitate severe haemolysis and methaemoglobinaemia; screen at-risk patients before use.
• Hypersensitivity and anaphylaxis can occur, so administer under appropriate supervision with resuscitation facilities available.
• Blood samples for uric acid measurement require special handling on ice, as rasburicase continues to degrade urate in vitro and falsely lowers results.

Monitoring

Monitor uric acid (using correctly handled samples), renal function and signs of haemolysis or hypersensitivity during therapy.

Counselling the patient

• Tell your team immediately if you feel breathless, develop a rash, or feel unwell during the infusion.
• This treatment helps protect your kidneys when there is rapid breakdown of cancer cells.

Evidence & guidelines

Rasburicase is recommended for the management of tumour lysis syndrome and is more effective than allopurinol at controlling urate, as shown in randomised trials.