Chemotherapy is the treatment of cancer using anti-cancer (cytotoxic) drugs. The aim is to kill cancer cells while doing the least possible damage to normal cells.

On this page, you can find the following information:

Cancer cells are cells in our body that divide and multiply quickly in an uncontrolled fashion. These cells can form a lump or mass that keeps getting bigger and bigger (local spread) and can also travel to other parts of the body through the lymphatic system and bloodstream (metastatic spread).

How does chemotherapy work?

Chemotherapy drugs travel through the bloodstream and kill cells in the body that grow quickly (such as cancer cells). They also kill fast-growing normal cells. This is why they cause major side effects throughout the body.

Fortunately, our bodies are amazing at healing and even when normal cells are damaged, they grow again. Damaged cancer cells are less likely to grow back and this is why chemotherapy can slow or cure the spread of cancer.

What does chemotherapy do?

Depending on your type of cancer and how advanced it is, chemotherapy can:

Cure cancer

When chemotherapy destroys cancer cells to the point that your doctor can no longer detect them in your body and they will not grow back.

Control cancer

When chemotherapy keeps cancer from spreading, slows its growth, or destroys cancer cells that have spread to other parts of the body.

Ease cancer symptoms

When chemotherapy shrinks tumours that are causing pain or pressure.

How is chemotherapy given?

Sometimes one type of chemotherapy drug is given by itself, either as tablets or capsules, or in a drip (intravenous or IV infusion). More often, two or more drugs are given together.

Chemotherapy drugs do not get into the brain, spinal cord or fluid bathing the brain and spinal cord very well, so for a few cancers, the drugs are inserted into the base of the spine through a process called lumbar puncture.

Is chemotherapy painful?

Having chemotherapy does not usually hurt. If you have a drip you will feel a brief sting as the needle goes in, but then the pain should stop. However, if the pain continues, or starts during the infusion, let the doctor or nurse know immediately.

Will I have to stay in hospital?

Most people have their chemotherapy as an outpatient. Usually you have to spend a few hours at the hospital for each treatment. This is because you often have to have a blood test first, and your doctors must wait for the result to check your blood count is okay before they can give you the treatment. Some people stay in hospital overnight or for two or three days.

If you live a long way from the hospital, you will probably be able to stay free of charge or at low cost at a comfortable hostel or motel. Family members can stay (at a reduced rate) in some hostels.

How is the type of chemotherapy chosen?

The type of treatment that your specialist chooses for you depends on:

  • what type of cancer you have
  • how far it has spread
  • your general health.

Chemotherapy has been used for many years, and new and better treatments are being discovered all the time, so your doctors will select the best treatment for you and your type of cancer.

Your doctors will keep a close eye on you during your treatment. You may have blood tests, x-rays and scans to see how you are doing.

If necessary, your doctors will change your drugs or how they give them to you. Sometimes they will stop the treatment early or continue it for longer than planned. It all depends on how your body and the cancer respond to the treatment.

How long will treatment last?

Your treatment could last several weeks or several months. You will probably get one dose of treatment at a time or over a few days, and then you will be given a rest before having the next treatment. Treatment cycles are usually two to four weeks apart. Spacing out your treatment in this way gives your body a chance to recover from any side effects.

Blood tests monitor cell counts

Before you have each treatment, a blood sample will be taken. This test (known as a blood count) measures the different cells in your blood. You need to have blood counts because chemotherapy drugs can lower blood cell levels.

If any part of your blood count is too low, your doctors might give you a longer time between treatments, they may change your drugs or give you additional treatment that boosts blood counts. 

Chemotherapy can help other treatment

Chemotherapy can be used alone, or sometimes it is started after surgery, when a tumour is removed. In this way, the chemotherapy kills any cancer cells that were not removed during surgery.

Sometimes chemotherapy is given before surgery or radiation, to make the cancer smaller, so that these treatments are likely to work better.


In terms of carrying out other activities while being treated, do only what you feel comfortable doing. You may find you can go on with your normal life, or that you have to take things much easier. The important thing is to look after yourself during chemotherapy so that your body is strong enough to cope with the drugs.

Do not do anything that you do not need to. Put your own needs and wishes first.

Most people keep working during their chemotherapy and arrange time off to go to hospital for each treatment. Some people work part time instead of full time, while others take a few days off around each treatment. Others take an extended break for the whole course of the treatment.

Talk to your employer, family and friends and work out what suits you. Do not force yourself to do too much.

Tell your doctor about other medications

Before you start chemotherapy, give your specialist a list of all the medications that you are taking, including occasional paracetamol (eg, Panadol), aspirins, anti-inflammatories (eg, Nurofen), vitamins, or treatments from herbalists, naturopaths, homoeopaths, etc.

If you want to take any new medications while having chemotherapy, ask your specialist about these before you begin taking them. Some chemotherapy drugs do not mix well with other medicines.

Can I drink alcohol?

It is usually fine to drink a little alcohol during treatment, but check with your specialist first – some chemotherapy drugs do not mix well with alcohol.

Can I drive?

You will probably find it best to get someone to drive you to and from hospital for the first treatment, as you might not feel well enough to drive. If you feel okay to drive after your first treatment, you will probably be fine to do so for following appointments.

Does chemotherapy cause cancer?

Some people who have chemotherapy may get another form of cancer much later in life. However, this rarely happens, and it is much more likely that your treatment will either cure you or control your cancer. If this question concerns you, talk it over with your specialist.


Emotions and cancer Cancer Society of NZ, 2010
How we can help? Wide range of support options Cancer Society of NZ
NZ cancer services – find a hospital/service near you Healthpoint, NZ
Questions you may wish to ask about chemotherapy Cancer Society of NZ
More cancer support groups

Credits: Provided by the Cancer Society of New Zealand. Reviewed By: Health Navigator NZ Last reviewed: 01 Jun 2014