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Cyclophosphamide will be prescribed for you by a specialist doctor.

Please keep your regular appointments with your doctor or hospital. You will need to have frequent blood tests while you are on cyclophosphamide.

Drink plenty of water and try to pass urine as often as possible.

This medicine lowers your natural protection against infection. It is important to protect yourself from serious illness by having any vaccinations your doctor offers you.

If you think you are getting an infection or if you have a high temperature, please see your doctor straightaway.

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About cyclophosphamide

Type of medicine

A chemotherapy and immunosuppressant medicine

Used for

Cancer; life-threatening connective tissue diseases such as severe rheumatoid arthritis

Available as

Tablets and injection

Cyclophosphamide is used to treat a variety of different cancers. It is also occasionally used to treat severe symptoms of some connective tissue diseases (such as rheumatoid arthritis) although these are not cancers.

In cancer, certain cells in the body grow and multiply too fast. Chemotherapy medicines like cyclophosphamide work by preventing cells from multiplying. This reduces the number of cancer cells made. Cyclophosphamide is often given alongside other medicines to help treat cancer.

Cyclophosphamide is also an immunosuppressant, which means that it suppresses your body's immune or defence system. Because of this, it is sometimes used to treat severe symptoms of conditions such as rheumatoid arthritis. The rest of this document is about cyclophosphamide when it is prescribed for cancer, so if you have been given it for a condition like rheumatoid arthritis, please speak with your doctor if you have any questions.

Before taking cyclophosphamide

Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you start taking cyclophosphamide it is important that your doctor knows:

  • If you are pregnant or breastfeeding.

  • If you have any problems with the way your kidneys work, or any problems with the way your liver works.

  • If you have an infection or feel unwell.

  • If you have noticed any blood in your urine.

  • If you have diabetes (diabetes mellitus).

  • If you have a rare inherited blood disorder called porphyria.

  • If you have ever had an allergic reaction to a medicine.

  • If you are taking any other medicines. This includes any medicines you are taking which are available to buy without a prescription, as well as herbal and complementary medicines.

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How to take cyclophosphamide

  • Before you start the treatment, read any printed information you have been given by your doctor and the printed manufacturer's leaflet from inside the pack of tablets. These will give you more information about cyclophosphamide and will provide you with a full list of the side-effects which you may experience from taking it.

  • Cyclophosphamide will be prescribed for you by a specialist doctor who is experienced in treating your condition. Your doctor will calculate what dose is right for you and will tell you how to take it - it is important that you take the tablets exactly as your doctor tells you to. It is usual to take one dose of tablets a day. Your dose will be printed on the label of the pack to remind you about what the doctor said to you but if you are unsure about what to do, or if you have any other concerns, you should contact your doctor or hospital clinic for advice.

  • Swallow the tablet whole, with a full glassful of water. Do not break, crush or chew the tablets before you swallow.

  • Cyclophosphamide tablets are best taken early in the day about an hour before a meal. However, if your stomach feels queasy after taking the tablets, you may be better taking your doses after eating some food, as this can help prevent feelings of sickness.

  • While you are on cyclophosphamide, it is important that you drink plenty of fluid and that you pass urine frequently. Drinking lots of water and other fluids will help prevent a serious type of cystitis sometimes caused by this medicine.

  • If you are sick (vomiting) shortly after taking a dose, or if you forget to take a dose at the correct time, contact your doctor or clinic for advice on what to do. You will be told whether to take another dose straightaway, or to just take your next dose when it is due.

Getting the most from your treatment

  • You must try to keep your regular appointments with your doctor or hospital. This is so your doctor can check on your progress. You will need to have regular blood tests and check-ups during your treatment with cyclophosphamide.

  • It is important that you do not get pregnant or father a child while you are taking cyclophosphamide and for three months after stopping the treatment. Make sure you have discussed with your doctor which types of contraception are suitable for you and your partner. If you would like to have children in the future, you should ask your doctor for advice about family planning before you begin taking cyclophosphamide. This is particularly important if you are a man, as there is a risk of reduced male fertility or sterility with cyclophosphamide treatment.

  • This medicine lowers your natural protection against infection. It is important to protect yourself from serious illness by having any vaccinations your doctor offers you. If you live with other people they can also help protect you by having their own vaccinations.

  • Some vaccines may not be suitable for people with lowered immune systems. Always let the person vaccinating know that you are taking this medicine.

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Can cyclophosphamide cause problems?

Medicines used to treat cancer can have a number of side-effects, some of which can be delayed for several days or weeks after taking the medicine. Most chemotherapy medicines can lower the number of white cells in your blood, which increases the risk of you getting an infection. While you are taking cyclophosphamide you should take precautions to reduce the risk of getting an infection - you can do this by avoiding being with people who you know have an infection. If you think you are getting a sore throat or if you have a high temperature, please let your doctor know as soon as possible so that you can get some treatment straightaway.

Your doctor will discuss with you the possibility of unwanted side-effects from your treatment with cyclophosphamide, although not everyone experiences these. The table below contains some of the side-effects associated with cyclophosphamide. You will find a full list in the manufacturer's information leaflet supplied with your medicine. Please let your doctor know if you experience any of the following:

Cyclophosphamide side-effects

What can I do if I experience this?

A high temperature, or symptoms of an infection

Let your doctor know about this straightaway

Feeling sick (nausea) or being sick (vomiting), loss of appetite

Stick to simple meals - avoid rich or spicy foods. Taking cyclophosphamide after food may help reduce feelings of sickness. If it becomes troublesome, let your doctor know

A burning feeling as you pass urine, blood in your urine

Continue to drink plenty of water and try to pass urine frequently. If you notice blood in your urine, please let your doctor know straightaway

Passing less urine than you would expect, swollen ankles

Let your doctor know about this as soon as possible. You may need to take another medicine to help with this

Skin rash with spots or blisters, sometimes with flu-like symptoms

Let your doctor know about this straightaway. It could be a sign of a rare but serious skin condition

Hair loss, flushing, weight loss, feeling short of breath, discolouring of your palms and nails, sore mouth, effects on your blood cells. In women, periods may stop. In men, sperm production may be reduced or stopped

Your doctor will talk to you about these

If you experience any other symptoms which you think may be due to cyclophosphamide, please speak with your doctor or pharmacist for further advice.

How to store cyclophosphamide

  • Keep all medicines out of the reach and sight of children.

  • Store in a cool, dry place, away from direct heat and light.

Important information about all medicines

Important information about all medicines

Never take more than the prescribed dose. If you suspect that you or someone else might have taken an overdose of this medicine, go to the accident and emergency department of your local hospital. Take the container with you, even if it is empty.

This medicine is for you. Never give it to other people even if their condition appears to be the same as yours.

If you are having an operation or dental treatment, tell the person carrying out the treatment which medicines you are taking.

If you buy any medicines, always check with a pharmacist that they are suitable for you to take with your prescribed medicines.

Do not keep out-of-date or unwanted medicines. Take them to your local pharmacy which will dispose of them for you.

If you have any questions about this medicine ask your pharmacist.

Report side effects to a medicine or vaccine

If you experience side effects, you can report them online through the Yellow Card website.

Further reading and references

Article history

The information on this page is written and peer reviewed by qualified clinicians.

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