Introduction

Asparaginase is chemotherapy that is given as a treatment for some types of cancer. This factsheet describes asparaginase, how it is given and some of its possible side effects. It should ideally be read with CancerBACUPs booklet Understanding chemotherapy, which gives more information and advice.

Each persons reaction to chemotherapy is unique. Some people have very few side effects, while others may experience more. The side effects described in this factsheet will not affect everyone who is given asparaginase, and may be different if you are having more than one chemotherapy drug.

We have outlined the commonest and less common side effects, so you can be aware of them if they occur. However, we have not included those which are very rare and therefore extremely unlikely to affect you. If you do notice any effects which you think may be due to the drug, but which are not listed in the factsheet, please discuss these with your doctor or chemotherapy nurse.

You will see your doctor regularly while you have this treatment so that s/he can monitor the effects of the chemotherapy. This factsheet should help you to discuss any queries about your treatment and its side effects with your doctor or chemotherapy nurse, as they are in the best position to help and advise you.

What it looks like

A white fluid after being dissolved from powder.

How it is given

• By injection into the vein (intravenously) through a cannula (a fine tube inserted into the vein). It may be given through a central line which is inserted under the skin into a vein near the collarbone.

• As an infusion (drip) through a cannula.

• By injection into a muscle (intramuscular).

Possible side effects

Nausea and vomiting. There are now very effective anti-sickness drugs to prevent or substantially reduce nausea and vomiting. If it does happen it may begin a few hours after the treatment is given and last for a few days. If the sickness is nt controlled, or continues, tell your doctor. S/he can prescribe other anti-sickness drugs which may be more effective.

Loss of appetite. A dietitian or specialist nurse at your hospital can give advice. CancerBACUP has a booklet called Diet and the cancer patient which has tips on boosting appetite, coping with eating difficulties and maintaining weight. We would be pleased to send this to you.

Changes in blood clotting. The liver produces substances which affect blood clotting. Asparaginase causes either more or fewer blood clotting factors to be produced. If fewer blood clotting factors are produced there may be a slight chance of more bleeding or bruising than usual, although this is not common. Tell your doctor about any bleeding or bruising. If too many clotting factors are produced there may be a risk of blood clots (thrombosis). Tell your doctor as soon as possible if you have any pain, heat, redness or swelling in a limb. Also let him/her know about any headache, nose bleeds, dizziness or feelings of confusion.

Fertility. Your ability to conceive or father a child may be affected by taking this drug. It is important to discuss fertility with your doctor before starting treatment.

Contraception. It is not advisable to become pregnant or father a child while taking asparaginase as it may harm the developing foetus. Again, discuss this with your doctor.

Your liver may be temporarily affected. Asparaginase may cause changes in liver function, which return to normal when the treatment is finished. This is very unlikely to cause you any harm, but your doctor will monitor this carefully. Samples of your blood will be taken from time to time to monitor your liver function.

Less common side effects

Temporary reduction in bone marrow function. This can result in anaemia, risk of bruising or bleeding, and infection. This effect can begin about 7 days after the treatment has been given and usually reaches its lowest point at 10-14 days after the chemotherapy. Your blood count will then increase steadily and will usually return to normal within 21-28 days.

The extent to which your blood count is reduced depends on the dose of chemotherapy you receive and which other chemotherapy drugs, if any, are given in combination. Your doctor can advise you how likely it is that your blood count will be lowered by the chemotherapy. Your blood count will be checked regularly to see how well your bone marrow is working.

If your temperature goes above 38C (100.5F), or you develop any unexplained bruising or bleeding, or you suddenly feel unwell, even with a normal temperature, contact your doctor or the hospital straightaway.

Increase in blood sugar. Asparaginase may cause a temporary increase in blood sugar levels. This is caused by its effect on the production of insulin by the pancreas. Insulin is a hormone that regulates the levels of sugar in the blood. Your blood sugar levels will be checked by regular blood tests, and you may be taught how to test your own levels at home. Some signs of a raised blood sugar level are: feeling thirsty, needing to pass urine more often, and increased appetite. If you have any of these let your doctor or nurse know.

Very rarely, inflammation of the pancreas occurs. This would cause a sharp pain. Tell your doctor about any pain so that appropriate medicine can be prescribed.

Fever and chills may occur from the time that the drug is given but they do not usually last long. Your doctor may prescribe medicines to reduce this side effect.

Allergic reaction. Signs of an allergic reaction include skin rashes and itchin, high temperature, shivering, redness of the face, a feeling of dizziness, headache, shortness of breath, anxiety, and a need to pass urine. You will be monitored for any signs of an allergic reaction during the treatment. Tell your doctor or nurse if you have any of these symptoms.

Lethargy, sleepiness and confusion. These are very rare. If you notice any of these effects it is important to tell your doctor.

Additional information

Sometimes people may experience an ache along the vein when the drug is being given.

Some other medicines can be harmful when you are having chemotherapy. Always tell your doctor about any other medicine you are taking.

We would like to thank the patients and specialist advisors who have helped with the production of this factsheet.

Last reviewed/updated September 1999