Side effects of chemotherapy for primary brain tumours

Chemotherapy can cause side effects. Your doctor can prescribe medicines to control some of these. Your nurse will also give you advice. Always tell them about your side effects.

Chemotherapy can reduce the number of white blood cells making you more at risk of getting an infection. If you have a high temperature or any signs of infection, contact the hospital straight away. It can also reduce the number of red blood cells making you feel tired and breathless. If the drugs reduce the platelet cells in your blood, you may bruise or bleed more easily. You will have blood tests before treatment to make sure your cells have recovered.

Feeling sick is another side effect but your doctor can give you anti-sickness drugs. Tiredness is very common. Try to pace yourself and get plenty of rest. It’s unusual to lose all your hair with the chemotherapy drugs used but your hair may become thinner.

If you are worried about the effects of chemotherapy on your fertility, talk to your specialist before treatment starts. You need to use effective contraception during chemotherapy.

Can you spare 5 minutes to help us improve our information about brain cancer? Please fill in our brain tumours information survey

Side effects of chemotherapy

Chemotherapy can cause side effects. These can often be managed or controlled with drugs and usually gradually improve after treatment has finished. Different drugs cause different side effects. Your cancer doctor or nurse will explain what to expect in your situation.

The main side effects are described here, as well as some ways to reduce or control them. You may get some of these side effects but you are very unlikely to get them all. Always tell your cancer doctor or nurse about any side effects so they can help.

Risk of infection

This treatment can reduce the number of white blood cells in your blood. These cells fight infection. If the number of white blood cells is low, you are more likely to get an infection. A low white blood cell count is called neutropenia.

If you have an infection, it is important to treat it as soon as possible. Contact the hospital straight away on the 24-hour contact number you have if:

  • your temperature goes over 37.5°C (99.5°F)
  • you suddenly feel unwell, even with a normal temperature
  • you have symptoms of an infection.

Symptoms of an infection include:

  • feeling shivery
  • a sore throat
  • a cough
  • diarrhoea
  • needing to pass urine often.

It is important to follow any specific advice your cancer treatment team gives you.

The number of white blood cells will usually return to normal before your next treatment. You will have a blood test before having more treatment. If your white blood cell count is low, your doctor may delay your treatment for a short time.

Anaemia (reduced number of red blood cells)

Chemotherapy may reduce the number of red blood cells (haemoglobin) in your blood. A low level of red blood cells is known as anaemia, which can make you feel very tired and lethargic. You may also become breathless.

Bruising and bleeding

Platelets are cells that help the blood to clot. If the number of platelets in your blood is reduced, you may bruise very easily or bleed more than usual from minor cuts or grazes. Tell your hospital doctor or nurse about this. Contact them straight away if you have nosebleeds, bleeding gums or tiny red or purple spots on the skin (called petechiae).

Feeling sick (nausea) and vomiting

Some chemotherapy drugs can make you feel sick (nauseated) or possibly be sick (vomit). Your cancer specialist will prescribe anti-sickness (anti-emetic) drugs to prevent this. Let your doctor or nurse know if your anti-sickness drugs are not helping, as there are different types you can try.

Tiredness (fatigue)

You are likely to become more tired as treatment goes on and you will have to take things slowly. Try to pace yourself and save your energy for things that you want to do or that need doing. Balance rest with some physical activity – even going for short walks will help you to feel less tired. We have more information about fatigue that may help. 

Hair loss

The chemotherapy drugs used to treat brain tumours may cause hair thinning. Complete hair loss is uncommon. Hair starts to grow back within about three to six months of the end of treatment. Your nurse can give you advice about coping with hair loss and how to look after your scalp. We have more information on coping with hair loss.

Effects of chemotherapy on fertility


Your doctor will advise you not to become pregnant or father a child while having chemotherapy. This is because the drugs may harm a developing baby. It’s important to use contraception during and for a few months after chemotherapy. You can discuss this with your doctor or specialist nurse.

Protecting your partner

If you have sex in the first couple of days of having chemotherapy, you need to use a condom. This is to protect your partner in case there is any chemotherapy in semen or vaginal fluid. Cancer cannot be passed on to your partner and sex won’t make the cancer worse.


Unfortunately, some chemotherapy drugs can cause infertility. Infertility is the inability to become pregnant or to father a child. This may be temporary or permanent, depending on the treatment that you have.

It is important to discuss your infertility risk with your cancer doctor before you start chemotherapy. If you have a partner, it’s a good idea to include them in this discussion. We have information about the effects of cancer treatment on fertility for women and men.

Back to Side effects of chemotherapy

Late effects of chemotherapy

Late effects are side effects you still have six months after chemotherapy, or side effects that begin years later.