Cyclophosphamide (pronounced sigh-clo-fos-fah-mide) is a type of chemotherapy. It is a treatment for a number of different types of cancer.
You can have cyclophosphamide on its own, or in combination with other chemotherapy drugs.
How cyclophosphamide works
Cyclophosphamide works by damaging the DNA of cancer cells. The DNA is the genetic material of cells.
How you have cyclophosphamide
You have cyclophosphamide as a drip into your bloodstream (intravenously) or as tablets that you swallow whole with plenty of water.
Into your bloodstream
You might have treatment through a long plastic tube that goes into a large vein in your chest. The tube stays in place throughout the course of treatment. This can be a:
- central line
- PICC line
If you don't have a central line
You might have treatment through a thin short tube (a cannula) that goes into a vein in your arm. You have a new cannula each time you have treatment.
Taking your tablets
You should take the right dose, not more or less.
Talk to your healthcare team before you stop taking a cancer drug, or if you miss a dose.
When you have cyclophosphamide
You have cyclophosphamide as cycles of treatment. Your plan depends on the type of cancer you have. And whether you’re having cyclophosphamide on its own or with other chemotherapy drugs.
Your doctor or nurse will tell you how often you’ll have it.
You have blood tests before and during your treatment. They check your levels of blood cells and other substances in the blood. They also check how well your liver and kidneys are working.
How often and how severe the side effects are can vary from person to person. They also depend on what other treatments you're having.
When to contact your team
Your doctor, nurse or pharmacist will go through the possible side effects. They will monitor you during treatment and check how you are at your appointments. Contact your advice line as soon as possible if:
- you have severe side effects
- your side effects aren’t getting any better
- your side effects are getting worse
Early treatment can help manage side effects better.
We haven't listed all the side effects here. Remember it is very unlikely that you will have all of these side effects. But you might have some of them at the same time.
Common side effects
These side effects happen in more than 10 in 100 people (more than 10%). You might have one or more of them. They include:
Increased risk of infection
Increased risk of getting an infection is due to a drop in white blood cells. Symptoms include a change in temperature, aching muscles, headaches, feeling cold and shivery and generally unwell. You might have other symptoms depending on where the infection is.
Infections can sometimes be life threatening. You should contact your advice line urgently if you think you have an infection.
Breathlessness and looking pale
You might be breathless and look pale due to a drop in red blood cells. This is called anaemia.
Bruising, bleeding gums or nose bleeds
This is due to a drop in the number of platelets in your blood. These blood cells help the blood to clot when we cut ourselves. You may have nosebleeds or bleeding gums after brushing your teeth. Or you may have lots of tiny red spots or bruises on your arms or legs (known as petechiae).
You could lose all your hair. This includes your eyelashes, eyebrows, underarms, legs and sometimes pubic hair. Your hair will usually grow back once treatment has finished but it is likely to be softer. It may grow back a different colour or be curlier than before.
Inflammation of the bladder
Inflammation of the bladder (cystitis) can cause pain and occasionally blood when passing urine.
You should drink 8 to 12 cups of fluid a day to try to prevent this.
Depending on the dose of cyclophosphamide you have, you might have extra fluids through a drip to prevent bladder irritation. Or you might have a drug called mesna to protect your bladder.
Occasional side effects
These side effects happen in between 1 and 10 out of every 100 people (between 1 and 10%). You might have one or more of them. They include:
- liver changes that are usually mild – you have regular blood tests to check this
- a sore mouth
- low sperm count in men
- lack of energy and strength
Rare side effects
This side effects happens in fewer than 1 in 100 people (fewer than 1%). You might have one or more of them. They include:
- an allergic reaction causing a skin rash, itching, swelling of the lips, face or throat, or breathing difficulties
- heart problems such as changes to the heart muscle or rhythm
- nerve pain or changes that can cause a lack of sensation and strength in the hands and feet
- loss of appetite
- hearing loss
- second cancers such as acute leukaemia or bladder cancer
- lung changes that can cause a cough or shortness of breath
- blood clots that are life threatening; signs are pain, swelling and redness where the clot is. Feeling breathless can be a sign of a blood clot on the lung. Contact your advice line or doctor straight away if you have any of these symptoms
- eye problems causing vision changes and discomfort
- skin and nail problems including a rash and colour changes
- irregular or no periods
Other side effects
There isn’t enough information to work out how often these side effects might happen. You might have one or more of them. They include:
- ringing in the ears (tinnitus)
- changes in blood sugar levels
- feeling confused
- inflammation of the lining of the large bowel (colitis)
What else do I need to know?
Other medicines, foods and drink
Cancer drugs can interact with some other medicines and herbal products. Tell your doctor or pharmacist about any medicines you are taking. This includes vitamins, herbal supplements and over the counter remedies.
Grapefruit and grapefruit juice
You should not eat grapefruit or drink grapefruit juice when you are taking this drug because it may increase the side effects.
Your doctor may tell you not to drink alcohol while having cyclophosphamide as a tablet. Alcohol might change the way this drug works and may increase feeling or being sick (nausea and vomiting).
Pregnancy and contraception
This treatment may harm a baby developing in the womb. It is important not to become pregnant or father a child while you are having treatment.
Women must not become pregnant for at least a year after the end of treatment. Men should not father a child for at least 6 months after treatment.
Talk to your doctor or nurse about effective contraception before starting treatment. Let them know straight away if you or your partner falls pregnant while having treatment.
Loss of fertility
You may not be able to become pregnant or father a child after treatment with this drug. Talk to your doctor before starting treatment if you think you may want to have a baby in the future.
Men might be able to store sperm before starting treatment. And women might be able to store eggs or ovarian tissue. But these services are not available in every hospital, so you would need to ask your doctor about this.
Don’t breastfeed during this treatment because the drug may come through into your breast milk.
Treatment for other conditions
Always tell other doctors, nurses, pharmacists or dentists that you’re having this treatment. For example, if you need treatment for anything else, including teeth problems.
Don’t have immunisations with live vaccines while you’re having treatment and for up to 12 months afterwards. The length of time depends on the treatment you are having. Ask your doctor or pharmacist how long you should avoid live vaccinations.
In the UK, live vaccines include rubella, mumps, measles, BCG, yellow fever and one of the shingles vaccines called Zostavax.
You can have:
- other vaccines, but they might not give you as much protection as usual
- the flu vaccine (as an injection)
- the coronavirus (COVID-19) vaccine - talk to your doctor or pharmacist about the best time to have it in relation to your cancer treatment
Members of your household who are aged 5 years or over are also able to have the COVID-19 vaccine. This is to help lower your risk of getting COVID-19 while having cancer treatment and until your
Contact with others who have had immunisations - You can be in contact with other people who have had live vaccines as injections. Avoid close contact with people who have recently had live vaccines taken by mouth (oral vaccines) such as the oral typhoid vaccine. Sometimes people who have had the live shingles vaccine can get a shingles type rash. If this happens they should keep the area covered.
If your immune system is severely weakened, you should avoid contact with children who have had the flu vaccine as a nasal spray as this is a live vaccine. This is for 2 weeks following their vaccination.
Babies have the live rotavirus vaccine. The virus is in the baby’s poo for about 2 weeks and could make you ill if your immunity is low. Get someone else to change their nappies during this time if you can. If this isn't possible, wash your hands well after changing their nappy.
More information about this treatment
For further information about this treatment go to the electronic Medicines Compendium (eMC) website.
You can report any side effect you have to the Medicines Health and Regulatory Authority (MHRA) as part of their Yellow Card Scheme.
This page is due for review. We will update this as soon as possible.