Vincristine, actinomycin D (dactinomycin) and cyclophosphamide (VAC)

VAC is the name of a chemotherapy combination. It includes the drugs we list below, next to each drug, we have how you pronounce the drug name in brackets.

  • vincristine (vin-kris-teen)
  • actinomycin D (ak-tih-noh-my-sin), it is also known as dactinomycin and Cosmegen
  • cyclophosphamide (sigh-clo-fos-fah-mide)

It is a treatment for:

  • a type of bone cancer called Ewing sarcoma
  • soft tissue sarcomas such as desmoplastic small round cell tumour and rhabdomyosarcoma
  • desmoid-type fibromatosis, also called desmoid tumour

How does VAC work?

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

How do you have VAC?

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
  • portacath

How often do you have VAC?

You have VAC in cycles of treatment. This means that you have all the drugs and then have a rest to allow your body to recover.

Each cycle of VAC lasts 21 days (3 weeks).  

Ewing sarcoma, rhabdomyosarcoma and desmoid-type fibromatosis

You might have up to 7 cycles of VAC, taking around 5 months in total. 

Desmoplastic small round cell tumour

You have VAC for as long as it’s working and the side effects aren’t too bad.

You have each cycle of treatment in the following way:

Day 1
  • You have vincristine as a drip into your bloodstream over 5 to10 minutes.
  • You have actinomycin as a drip into your bloodstream over 30 minutes or as a slow injection into the bloodstream.
  • You have cyclophosphamide as a drip into your bloodstream over 3 hours.
Day 2
  • You have actinomycin as a drip into your bloodstream over 30 minutes or as a slow injection into the bloodstream.
Day 3 to day 21
  • You have no treatment.

You then start the next treatment cycle.

Mesna and G-CSF

You usually have cyclophosphamide with another drug called mesna. You have mesna either as a drip (infusion) into your bloodstream or as tablets.

Mesna is not a chemotherapy drug. It stops the cyclophosphamide from irritating your bladder and making the lining bleed.

You usually also have a drug called granulocyte colony stimulating factor (G-CSF). This makes your bone marrow Open a glossary item produce white blood cells Open a glossary item more quickly after the chemotherapy. It helps lower your risk of getting an infection after having this treatment.

Your healthcare team will tell you what day to start your G-CSF injections.


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.

What are the side effects of VAC?

Side effects 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. 

Contact your advice line immediately if you have signs of infection, including a temperature above 37.5C or below 36C.

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 (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. 

Rarely, you might get sepsis. This is a serious reaction to an infection. Signs can include feeling very unwell, not passing urine, being sick, a very high or very low temperature or shivering - contact your advice line straight away if you have any of these symptoms.

A sore mouth

You might get a sore mouth and mouth ulcers. It may be painful to swallow drinks or food. You will have mouth washes to keep your mouth healthy.

You can have painkillers to reduce the soreness. Take them half an hour before meals to make eating easier.

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).

Breathlessness and looking pale

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

Inflammation of the bladder

Inflammation of the bladder causes a burning feeling when passing urine and the need to pass urine often.

Less commonly, you might have damage to the lining of your bladder which can cause bleeding.

Let your doctor or nurse know if this happens and drink plenty of fluids.

Hair loss

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. 

High temperature (fever)

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


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.

Rarely, diarrhoea can be bloody with a fever and tummy (abdominal) pain. Contact your doctor or advice line if you have this


Constipation Open a glossary item is easier to sort out if you treat it early. Drink plenty of fluids and eat as much fresh fruit and vegetables as you can. Try to take gentle exercise, such as walking. Tell your healthcare team if you think you are constipated. They can prescribe a laxative.

Feeling or being sick

Feeling or being sick is usually well controlled with anti sickness medicines. It might help to avoid fatty or fried foods, eat small meals and snacks and take regular sips of water. Relaxation techniques might also 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 treat it once it has started.

Occasional side effects

These side effects happen in between 1 and 10 out of every 100 people (1 to 10%). You might have one or more of them. They include: 

  • changes to the way your liver works. Rarely, you might have inflammation of the liver (hepatitis) or blocking of the veins taking blood to the liver or an enlarged liver. You have regular blood tests to check for any changes in the way your liver is working
  • problems with sperm production
  • chills
  • weakness and feeling generally unwell
  • numbness or tingling in fingers or toes
  • changes to several nerves causing burning pain, a loss of a sense of vibration and position of the arms or legs. This might affect walking and standing

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 such as leukaemia, a rare blood cancer called myelodysplastic syndrome (MDS), bladder cancer or cancer of the tubes that carry urine from the kidneys to the bladder (ureters)
  • breakdown of tumour cells which can cause high levels of uric acid and other substances in your body
  • small blood clots developing throughout the bloodstream, blocking small blood vessels (disseminated intravascular coagulation)
  • kidneys stopping working or a condition where the small blood vessels in your kidneys become damaged and inflamed. You will have tests to check how well your kidneys work  
  • an allergic reaction which can be serious and life threatening. Symptoms can include a rash, shortness of breath, redness or swelling of the face, feeling hot, dizziness, and a sudden need to pass urine. Tell your doctor or nurse immediately if you have any of these symptoms or feel unwell at all while you are having the treatment or shortly afterwards
  • an excessive uncontrolled release of a hormone called antidiuretic hormone (ADH) causing low sodium levels. Symptoms include sickness, loss of appetite, sore muscles and weakness. You have regular blood tests to check your sodium levels
  • loss of appetite and taste changes
  • not having enough fluid in your body (dehydration)
  • pain along a nerve
  • fits (seizures)
  • changes to how your heart works, such as your heart rhythm. Tests such as a heart trace (ECG) might pick this up. Other changes include the heart muscle being unable to pump blood as well as it should (heart failure) or a heart attack. Symptoms of a heart attack include an overwhelming pain, heaviness, or tightness in the chest, feeling lightheaded or dizzy, pain in different parts of the body, sweating or feeling anxious. Other changes to the heart include inflammation of the heart muscle (myocarditis) or the thin layers of tissue around the heart (pericarditis), causing chest pain or shortness of breath.
  • flushing - sudden reddening and warmth of the neck, upper chest and face
  • high blood pressure that might cause headaches, confusion, vision problems or chest pain or low blood pressure that can cause you to feel lightheaded or dizzy
  • 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 in the lung. Contact your advice line or doctor straight away if you have any of these symptoms
  • lung changes such as a build up of fluid in the lung, scarring of the lung or tightening of the airways causing difficulty breathing and less oxygen reaching your bloodstream
  • inflammation of the pancreas causing tummy pain, a fever, a fast heart rate and feeling or being sick
  • Stevens Johnson syndrome (SJS) or toxic epidermal necrolysis - a severe skin reaction that may start as tender red patches which lead to peeling or blistering of the skin. You might also feel feverish, and your eyes may be more light sensitive. This is serious and could be life threatening
  • breakdown of muscle, causing sore muscles and dark urine
  • low levels of female sex hormones
  • several body parts (organs) stopping working
  • high levels of a substance (enzyme) called LDH in the blood. You will have blood tests to check this
  • hearing loss

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:

  • low calcium levels in the blood causing symptoms such as painful muscle spasms and cramps, twitching of muscles, numbness or tingling in feet and hands or around the mouth
  • a collapsed lung (pneumothorax) – symptoms include chest pain or shortness of breath
  • changes in the digestive system, such as stomach ulcers, inflammation of the food pipe or rectum
  • inflammation of the lips
  • difficulty swallowing
  • a build up of fluid in the tummy (ascites)
  • a build up of fluid around the lung (pleural effusion)
  • skin changes such as a rash, irritation, a reaction triggered by medicine or infection (erythema multiforme), acne or skin turning red or darker in areas of previous radiotherapy. Or you might have nail changes such as discolouration
  • slow growth
  • tiredness, lacking energy or a general feeling of discomfort
  • eye changes such as inflammation of the eye nerve causing pain and changes to vision or vision loss which is temporary
  • changes to your ears causing difficulty with balance, including dizziness, feeling like the room is spinning (vertigo) and uncontrolled eye movement (nystagmus)
  • tummy (abdominal) cramps. Tell your treatment team if you have this. They can check the cause and give you medicine to help
  • pain in your muscles and bones, including pain in your jaw or back. Speak to your doctor or nurse about what painkillers you can take to help with this
  • problems with passing urine, such as passing large amounts of urine, having discomfort when passing urine, or not being able to pass urine (urine retention)
  • swelling and pain at the drip site. Tell your nurse straight away if you have any pain, redness, swelling or leaking around your drip site
  • weight loss

If you have side effects that aren't listed on this page, you can look at the individual drug pages:

Coping with side effects

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

What else do you need to know?

Other medicines, foods and drinks 

Cancer drugs can interact with medicines, herbal products, and some food and drinks. We are unable to list all the possible interactions that may happen. An example is grapefruit or grapefruit juice which can increase the side effects of certain drugs.

Tell your healthcare team about any medicines you are taking. This includes vitamins, herbal supplements and over the counter remedies. Also let them know about any other medical conditions or allergies you may have.

Loss of fertility 

You may not be able to become pregnant or get someone pregnant 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 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.    

Contraception and pregnancy 

This treatment may harm a baby developing in the womb. It is important not to become pregnant or get someone pregnant while you are having treatment. Women must not become pregnant for at least a year after the end of treatment. Men should not get someone pregnant 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 become pregnant while having treatment.


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

Treatment for other conditions 

If you are having tests or treatment for anything else, always mention your cancer treatment. For example, if you are visiting your dentist.


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 immune system Open a glossary item recovers from treatment.

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 and possible side effects go to the electronic Medicines Compendium (eMC) website. You can find the patient information leaflet on this website.

You can report any side effect you have to the Medicines Health and Regulatory Authority (MHRA) as part of their Yellow Card Scheme.

Related links