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Cytoxan Print


Generic name: cyclophosphamide
Trade name: Cytoxan
Other names: Neosar
Drug type:
Cyclophosphamide is a chemotherapy drug used to treat some types of cancer, including breast cancer, lung cancer, and some lymphomas and leukaemias. It works by sticking to one of the cancer cell's DNA strands(the cell's genetic code) so the cell can't divide into 2 new cells. DNA is the genetic code in the nucleus of all animal and plant cells. It controls everything the cell does.

How you have treatment

You usually have cyclophosphamide as an injection into a vein. It also comes as tablets that you swallow, ideally on an empty stomach. You usually have chemotherapy as a course of several cycles of treatment. The treatment plan for cyclophosphamide depends on which cancer you are being treated for. There is more about planning chemotherapy in the main chemotherapy section of CancerHelp UK.

The side effects associated with cyclophosphamide are listed below. You can use the links (underlined) to find out more about each side effect. Where there is no link, look in our chemotherapy side effects section or use the search box at the top of the page.

Common side effects

Many people experience a temporary drop in the number of blood cells made by your bone marrow, leading to the following side effects

  • Increased risk of getting an infection from a drop in white blood cells – it is harder to fight infections and you can become very ill. You may have headaches, aching muscles, a cough, sore throat, pain passing urine or feel cold and shivery. Infections can sometimes be life threatening. You should contact your treatment centre straight away if you think you have an infection
  • Tiredness and breathlessness due to a drop in red blood cells (anaemia) – you may need a blood transfusion
  • Bruising more easily due to a drop in platelets – you may have nosebleeds, bleeding gums after brushing your teeth, or lots of tiny red spots or bruises on your arms or legs (known as petechia). You should contact your treatment centre if you have any of these effects

Other common side effects include

  • Fatigue during and after treatment – most people find their energy levels are back to normal within 6 months to a year
  • Nausea and vomiting – this is usually mild
  • Loss of appetite
  • Hair loss or hair thinning usually starts about 3 to 4 weeks after your first dose – a cold cap may help to stop you losing your hair, but you need to talk to your doctor about how advisable this is with your type of cancer
  • Women may stop having periods (amenorrhoea) but this may only be temporary
  • Loss of fertility – you may not be able to get pregnant or father a child after treatment with this drug. It is important to talk to your doctor about fertility before starting treatment.
  • Cyclophosphamide may have a harmful effect on a developing baby – do talk to your doctor about contraception before having treatment if there is any chance that you or your partner could become pregnant

Occasional side effects

Some people have the following side effects:

  • Diarrhoea – you should drink plenty of fluids. If your diarrhoea is severe or continues you could become dehydrated so let your doctor or nurse know
  • Your nails may darken or become ridged
  • Your skin may darken
  • Mouth ulcers
  • Cystitis (inflammation of the bladder) can cause pain and occasionally blood when passing urine. If you see blood in your urine contact your doctor straight away. You should drink 8 to 12 cups of fluid a day. If you are having cyclophosphamide through a drip you will have extra fluids through the drip too.

Rare side effects

A very small number of people have these side effects

  • There is a small risk that you may get a second cancer some years after cyclophosphamide treatment
  • Damage to heart muscle which is usually temporary but for a small number of people may be permanent – your doctor will check your heart before and after your treatment
  • Changes in lung tissue may lead to a cough or breathlessness
  • Fluid retention

Important points to remember:

The side effects above may be mild or more severe. A side effect may get better or worse through your course of treatment, or more side effects may develop as the course goes on. This depends on:

  • How many times you've had the drug before
  • Your general health
  • The amount of the drug you have (the dose)
  • Other drugs you are having

Some side effects are inconvenient or upsetting but not damaging to your health. Some side effects are serious medical conditions and need treating. Where we have urged you to contact your doctor, this is because

  • Your side effect may need treating
  • Your drug dose may need reducing to try to prevent the side effect

Tell your doctor about any other medicines you are taking, including vitamins, herbal supplements and other over the counter remedies – some drugs can react together.

Talk to your doctor, pharmacist or nurse about all your side effects so that they can help you manage them. Your chemotherapy nurse, clinic or ward nurse will have given you a contact number. You can ring if you have any questions or problems. They can give you advice or reassure you. If in doubt, call them.

Immunisations and chemotherapy

You should not have immunisations with live vaccines while you are having chemotherapy or for at least 6 months afterwards. In the UK, these include rubella, mumps, measles (usually given together as MMR), BCG and yellow fever. You can have other vaccines, but they may not give you as much protection as usual until your immune system has fully recovered from your chemotherapy.

It is perfectly safe for you to be in contact with other people who've had live vaccines as injections. There can be problems with oral vaccines, but no one in the UK is given an oral vaccine now. So there is no problem in being with any baby or child who has recently had any vaccination in the UK. If you live abroad, you might need to make sure that you aren't in contact with anyone who has had oral polio or oral typhoid vaccination recently.

Last Updated on Thursday, 21 January 2010 08:49