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CMF

CMF is the name of a chemotherapy combination that includes:

  • cyclophosphamide
  • methotrexate
  • fluorouracil (5FU)

It is a treatment for breast cancer.

How CMF works

These chemotherapy drugs destroy quickly dividing cells, such as cancer cells.

How you have CMF

You usually have cyclophosphamide, methotrexate and fluorouracil as drips or injections into your bloodstream (intravenously). You may also have cyclophosphamide as tablets.

Drugs into your bloodstream

You have the treatment through a drip into your arm or hand. A nurse puts a small tube (a cannula) into one of your veins and connects the drip to it.

You might need a central line. This is a long plastic tube that gives the drugs into a large vein, either in your chest or through a vein in your arm. It stays in while you’re having treatment, which may be for a few months.

Taking tablets

You must take tablets according to the instructions your doctor or pharmacist gives you.

You should take the right dose, not more or less.

Talk to your specialist or advice line before you stop taking a cancer drug.

When you have CMF

You usually have CMF as cycles of treatment that last 4 weeks. A cycle of treatment means that you have treatment and then have a rest to allow your body to recover. 

You usually have 4 to 6 treatment cycles of CMF. You might have each cycle in the following way:

Day 1
  • You have cyclophosphamide as a drip or injection into your bloodstream (intravenously)
  • You have methotrexate as a drip into your bloodstream
  • You have fluorouracil as an injection into your bloodstream
Day 2 to day 7
  • You have no treatment
Day 8
  • You have cyclophosphamide as a drip or injection into your bloodstream
  • You have methotrexate as a drip into your bloodstream
  • You have fluorouracil as an injection into your bloodstream
Day 9 to day 28
  • You have no treatment

You then start a new treatment cycle. 

If you have cyclophosphamide as tablets, you take them once a day from day 1 to day 14 of each treatment cycle. 

Tests

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.

Side effects

We haven't listed all the side effects. It is very unlikely that you will have all of these side effects, but you might have some of them at the same time.

How often and how severe the side effects are can vary from person to person. They also depend on what other treatment you are having. For example, your side effects could be worse if you are also having other drugs or radiotherapy.

When to contact your team

Your doctor or nurse will go through the possible side effects. They will monitor you closely 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. 

Contact your advice line or your doctor or nurse immediately if you have signs of infection, such as a temperature above 37.5C or below 36C, or if you develop a severe skin reaction. Signs of a severe skin reaction include peeling or blistering of the skin.

Common side effects

These effects happen in more than 10 in 100 people (10%). You might have one or more of them. They include:

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 

You might be breathless and look pale due to a drop in red blood cells. This is called anaemia.

Bruising and bleeding 

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 petechia).

Hair loss

You could lose all your hair. This includes your eyelashes, eyebrows, underarm, leg 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 (cystitis)

You might feel that you have to pass urine more often than usual. And you may have a burning feeling when you do. Or you might feel that you can't wait when you need to go. This is called cystitis. 

You may also see blood when you pass urine. Let your doctor know if this happens. You should drink 8 to 12 cups of fluid every day. 

High temperature (fever) 

If you get a high temperature, let your treatment team know straight away. Ask them if you can take paracetamol to help lower your temperature.

Difficulty breathing 

You may have difficulty breathing with wheezing and coughing. Let your doctor or nurse know straight away if this happens. 

High levels of uric acid in your body 

High levels of uric acid in your blood can lead to a build up of crystals in body tissues and cause inflamed joints. You’ll have regular blood tests to check your levels. Drinking plenty of fluids helps to flush out the excess uric acid. You might also have medicines to control the uric acid levels.

Changes to the way your heart works

You might have heart changes that show up on a heart trace (ECG). You have regular tests throughout your treatment to check for this. Your doctor may stop treatment for a short time or may lower the dose if you have this. 

Feeling or being sick 

Feeling or being sick is usually well controlled with anti sickness medicines. Avoiding fatty or fried foods, eating small meals and snacks, drinking plenty of water, and relaxation techniques, can all help.

It is important to take anti sickness medicines as prescribed even if you don’t feel sick. It is easier to prevent sickness rather than treating it once it has started.

Loose or watery poo (diarrhoea) 

Contact your advice line if you have diarrhoea, such as if you've had 4 or more loose watery poos (stools) in 24 hours. Or if you can't drink to replace the lost fluid. Or if it carries on for more than 3 days.

Your doctor may give you anti diarrhoea medicine to take home with you after treatment. Eat less fibre, avoid raw fruits, fruit juice, cereals and vegetables, and drink plenty to replace the fluid lost.

Loss of appetite 

Feeling or being sick can be severe. It can start a few hours after treatment and last for a few days. Anti-sickness injections and tablets can control it. Contact your doctor or nurse straight away if you’ve been sick more than once in a day.

Mouth sores and ulcers 

Mouth sores and ulcers can be painful. Keep your mouth and teeth clean; drink plenty of fluids; avoid acidic foods such as oranges, lemons and grapefruits; chew gum to keep the mouth moist and tell your doctor or nurse if you have ulcers.

Tiredness (fatigue) 

You might feel very tired and as though you lack energy.

Various things can help you to reduce tiredness and cope with it, for example exercise. Some research has shown that taking gentle exercise can give you more energy. It is important to balance exercise with resting.

Slow wound healing 

This treatment can slow wound healing. If you need to have an operation you may need to stop taking it for a while beforehand. Your doctor will let you know when you can start taking it again.

Rare side effects

These side effects happen in fewer than 1 in 100 people (1%). You might have one or more of them. They include:

  • a second cancer some years after treatment has finished
  • breakdown of large numbers of tumour cells which can cause heart and kidney problems (tumour lysis syndrome)
  • an allergic reaction which can be life threatening
  • loss of fluid in your body (dehydration)
  • low levels of sodium which can cause weakness and headaches
  • confusion and dizziness
  • numbness or tingling in fingers and toes that can make it difficult to do fiddly things such as doing up buttons
  • taste changes
  • seizures (fits)
  • problems with your eyes such as blurred vision and redness or soreness
  • hearing loss
  • serious heart problems such as a heart attack
  • blood clots in the deep veins of your body
  • a build up of fluid in your tummy (abdomen)
  • constipation
  • changes in the way your liver works which are usually mild and temporary
  • skin rash, itchy skin and nail changes
  • a severe skin reaction that may start as tender red patches which leads to peeling or blistering of the skin. You might also feel feverish and your eyes may be more sensitive to light. This is serious and could be life threatening

Other side effects

For more information about the side effects of individual drugs:

Coping with side effects

We have more information about side effects and tips on how to cope with them.

What else do I need to know?

DPD deficiency

Between 2 and 8 out of 100 people (2 to 8%) have low levels of an enzyme called DPD in their bodies. A lack of DPD can mean you’re more likely to have severe side effects from fluorouracil. It doesn’t cause symptoms, so you won’t know if you have a deficiency. Talk to your doctor if you are worried about it.

Contact your doctor if your side effects are severe.

Other medicines, foods and drinks

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.

Contraception and pregnancy 

This treatment might harm a baby developing in the womb. It is important not to become pregnant or father a child while you're having treatment and for a few months afterwards. Talk to your doctor or nurse about effective contraception before starting treatment.

Loss of fertility 

You may not be able to become pregnant or father a child after treatment with these drugs. Talk to your doctor before starting treatment if you think you may want to have a baby in the future. Men may be able to store sperm before starting treatment. Women may be able to store eggs or ovarian tissue but this is rare.

Breastfeeding 

Don’t breastfeed during this treatment because the drugs may come through in your breast milk.

Treatment for other conditions 

Always tell other doctors, nurses, pharmacists or dentists that you’re having this treatment if you need treatment for anything else, including teeth problems.

Immunisations 

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 the shingles vaccine (Zostavax).

You can:

  • have other vaccines, but they might not give you as much protection as usual
  • have the flu vaccine (as an injection)
  • 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 oral polio or the typhoid vaccine.

This also includes the rotavirus vaccine given to babies. The virus is in the baby’s poo for up to 2 weeks and could make you ill. So avoid changing their nappies for 2 weeks after their vaccination if possible. Or wear disposable gloves and wash your hands well afterwards.

You should also avoid close contact with children who have had the flu vaccine nasal spray. You should do so for 2 weeks following their vaccination if you have a severely weakened immune system.

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.

Information and help