Rasburicase (Fasturtec®)

Rasburicase is a drug which can help prevent or reduce a side effect of chemotherapy called tumour lysis syndrome.

Tumour lysis syndrome can happen when you start chemotherapy treatment. As the cancer cells are destroyed by the chemotherapy drugs, they release a substance called uric acid. Usually the kidneys remove the uric acid. But if a lot of cancer cells are destroyed, there might be too much uric acid for the kidneys to cope with.

Rasburicase changes the uric acid so that the kidneys can remove it. Your nurse will give you rasburicase before or during your chemotherapy. It is given as a drip (infusion) into a vein.

Like other drugs, rasburicase can cause side effects. If these happen they are usually mild, but occasionally they can be severe. It is important to read the detailed information below so that you are aware of possible side effects. Tell your doctor or nurse if you notice any changes.

Tumour lysis syndrome

Tumour lysis syndrome (TLS) can be caused by some chemotherapy drugs.

Chemotherapy uses anti-cancer (cytotoxic) drugs to destroy cancer cells. As the cancer cells break down, they release a chemical called uric acid, which is removed from the body by the kidneys.

TLS can happen when lots of cancer cells are destroyed very quickly. The kidneys can't cope with the increased amount of uric acid. This leads to imbalances in some chemicals (phosphate, potassium and calcium) in the blood. These imbalances can cause more serious problems affecting the kidneys and the heart.

TLS is more common in cancers that grow quickly and respond quickly to chemotherapy, such as acute leukaemias and high-grade lymphomas. People with other types of cancer are rarely affected by TLS.

How rasburicase works

Rasburicase changes uric acid so that it can be easily processed and removed from the body by the kidneys. This prevents a build-up of uric acid.

How rasburicase is given

Rasburicase is given before or during the start of your chemotherapy treatment.

Your nurse will give you rasburicase through one of the following:

  • a short, thin tube (cannula) that the nurse puts into a vein in your arm or hand
  • a fine tube that goes under the skin of your chest and into a vein close by (central line)
  • a fine tube that is put into a vein in your arm and goes up into a vein in your chest (PICC line).

Your nurse will give you rasburicase as a drip into your vein. The infusion is given over 30 minutes. You may have one dose or a daily dose for up to seven days. Your doctors will decide how many days of treatment you need. They will do this by taking regular blood tests to check the level of uric acid in your blood.

You will also be given large amounts of fluids through a line into your bloodstream (called intravenous hydration) to help flush through your kidneys.

Possible side effects of rasburicase

Each person’s reaction to any medication is different. Most people have very few side effects, while others may experience more. The side effects described here won't affect everyone who is having rasburicase and may be different if you are having more than one drug.

We explain the most common side effects of rasburicase here. But we don’t include all the rare ones that are unlikely to affect you. For more detailed information you can visit the electronic Medicines Compendium.

If you notice any side effects that are not listed here, discuss them with your nurse or doctor.

Always tell your doctor or nurse about the side effects you have. Your nurse will give you telephone numbers for the hospital. You can call them if you feel unwell or need advice any time of day or night. Save these numbers in your phone or keep them somewhere safe.

High temperature

Your nurse will monitor your temperature during treatment with chemotherapy and rasburicase. Signs of a high temperature can include feeling hot and sweaty or feeling cold and shivery. It's important to let the nurse or doctor know if you feel you have a high temperature.

Allergic reaction

Rarely, rasburicase may cause an allergic reaction while it’s being given. Your nurse will check you for this. If you have a reaction, they will treat it quickly. Signs of an allergic reaction can include:

  • a rash
  • feeling itchy
  • feeling short of breath
  • chest pain.

Tell your nurse straight away if you have any of these symptoms.


If you have diarrhoea, your doctor can prescribe drugs to control it. Let them know if it is severe or if it doesn’t get better. Make sure you drink at least two litres (three and a half pints) of fluids every day if you have diarrhoea.

Feeling or being sick

Rasburicase may cause you to feel sick. Your doctor can prescribe very effective anti-sickness drugs (anti-emetics) to help prevent or reduce sickness. If you are sick after taking rasburicase, contact the hospital for advice.


This treatment may cause headaches. If this happens, tell your doctor or nurse. They can give you painkillers.

Blood changes

Rarely, rasburicase can increase the breakdown of red blood cells. You will have regular blood tests during your treatment to check for this side effect.

Additional information

Rasburicase should not be given to anyone who has the metabolic disorder known as glucose-6-phosphate dehydrogenase (G6PD) deficiency.

Some medicines can be harmful to take when you are having cancer treatment. Let your doctor know about any medication you are taking, including non-prescribed drugs such as over-the-counter medicines, complementary therapies and herbal drugs.