[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Pharmacology](https://durgical.com/en/pharmacology/) › [Chemotherapy supportive agents](https://durgical.com/en/pharmacology/classes/chemotherapy-supportive-agents/) › Rasburicase [Pharmacology](https://durgical.com/en/pharmacology/) · [Chemotherapy supportive agents](https://durgical.com/en/pharmacology/classes/chemotherapy-supportive-agents/) # Rasburicase A recombinant urate oxidase enzyme that turns uric acid into soluble allantoin in tumour lysis. It must not be given in G6PD deficiency. Updated 2026-11-01 - Class: [Chemotherapy supportive agents](https://durgical.com/en/pharmacology/classes/chemotherapy-supportive-agents/) - Target: Uric acid (the drug is the enzyme urate oxidase) - ATC code: V03AF07 - WHO Model List of Essential Medicines ◆**Uric acid (the drug is the enzyme urate oxidase)**Rasburicase ⓘ The structure shows urate oxidase from the mould Aspergillus flavus, the kind of enzyme rasburicase is, holding the inhibitor 8-azaxanthine in its urate-binding site. **Target in 3D:** Uric acid (the drug is the enzyme urate oxidase). PDB structure 1R51 (RCSB PDB, public domain). [View the structure at RCSB PDB](https://www.rcsb.org/structure/1R51) · Drag to rotate · pinch to zoom ## Mechanism of action Humans lack urate oxidase, so uric acid is the end product of purine breakdown. Rasburicase supplies the enzyme: it oxidises uric acid to allantoin, which is far more soluble and easily excreted. The reaction produces hydrogen peroxide; red cells with too little G6PD cannot neutralise it, leading to haemolysis and methaemoglobinaemia. - Tumour lysis floods the blood with uric acid - Rasburicase oxidises uric acid to allantoin - Soluble allantoin is excreted: kidneys protected - The H2O2 by-product is dangerous if G6PD is low ## Pharmacokinetics **Absorption** Intravenous infusion in hospital, as a single short course. ## Indications - High uric acid in people with certain cancers receiving chemotherapy, as tumour cells break down (tumour lysis). [Tumour lysis syndrome →](https://durgical.com/en/conditions/tumour-lysis-syndrome/) ## Adverse effects ### Common - Nausea, vomiting, diarrhoea or constipation, abdominal pain - Fever, headache, mouth sores - Swelling of the legs; pain or redness at the injection site ### Serious (rare, important) - Severe allergic reactions, including anaphylaxis - Haemolysis and methaemoglobinaemia, especially in G6PD deficiency (blue-grey skin, dark urine, jaundice, breathlessness) ## Contraindications - G6PD deficiency (people of African or Mediterranean ancestry are screened first) - Previous severe allergic reaction to rasburicase ## Key interactions **Uric acid laboratory tests** Rasburicase can affect the results; the laboratory is told the patient is receiving it. ## What is monitored - G6PD status before the first dose - Uric acid, potassium, phosphate, calcium and creatinine - Signs of haemolysis or methaemoglobinaemia (colour, oxygen saturation, urine) ## Administration and safety - Given by intravenous infusion in hospital; the infusion is stopped at once if an allergic reaction occurs. - Usually a single course that is not repeated. - Before uric acid samples are drawn, the laboratory is told that the patient is receiving rasburicase. ## Nursing care - Confirm the G6PD result before the first dose. - Watch for chest tightness, wheeze, hives or swelling of the lips during the infusion. - Watch skin colour and oxygen saturation; report dark urine, jaundice or confusion. - Strict intake and output during tumour lysis prevention. ## Memory aid RASBURicase «RAzes Uric acid» to allantoin, but leaves peroxide behind: «no G6PD, no rasburicase». ## Test yourself Think of the answer, then tap the question to see it. ## What does rasburicase convert uric acid into? Allantoin, which is much more soluble and easily excreted. ## Why is rasburicase dangerous in G6PD deficiency? The reaction makes hydrogen peroxide; G6PD-deficient red cells cannot neutralise it, causing haemolysis and methaemoglobinaemia. ## Why do humans need a drug to break down uric acid that many mammals break down themselves? Humans lack a functional urate oxidase (uricase), so uric acid is our end product of purine breakdown. [Add to my cards (3)](https://durgical.app/estudiar/?add=/en/pharmacology/rasburicase/) ## Related drugs - [Mesna](https://durgical.com/en/pharmacology/mesna/) - [Doxorubicin](https://durgical.com/en/pharmacology/doxorubicin/) ## Related conditions - [Tumour lysis syndrome](https://durgical.com/en/conditions/tumour-lysis-syndrome/) [← Back to the class: Chemotherapy supportive agents](https://durgical.com/en/pharmacology/classes/chemotherapy-supportive-agents/) Educational content on how drugs work; not a prescribing guide and no substitute for a health professional's advice. No doses are given. Sources: [Rasburicase Injection: MedlinePlus Drug Information](https://medlineplus.gov/druginfo/meds/a610008.html) (MedlinePlus (U.S. National Library of Medicine), 2016); Farmacología básica y clínica (Katzung), cap. 5 (McGraw Hill, 2025); Goodman & Gilman's The Pharmacological Basis of Therapeutics, 14th ed., ch. 7 (McGraw Hill, 2023); [ATCDDD - ATC/DDD Index](https://atcddd.fhi.no/atc_ddd_index/?code=V03AF07) (WHO Collaborating Centre for Drug Statistics Methodology, 2026). ## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake Representative model, for educational purposes only. --- Source: https://durgical.com/en/pharmacology/rasburicase/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/pharmacology/rasburicase/