What is chemotherapy?

Chemotherapy uses anti-cancer (cytotoxic) drugs to destroy cancer cells. Cytotoxic means toxic to cells. Most chemotherapy drugs are carried in the blood. This means they can reach cancer cells anywhere in the body. Chemotherapy is sometimes called systemic anti-cancer therapy (SACT).

Cytotoxic chemotherapy drugs disrupt the way cancer cells grow and divide. But they also affect some of the healthy cells in your body. These healthy cells can usually recover from damage caused by chemotherapy. But cancer cells cannot recover, and they eventually die.

Because chemotherapy drugs can affect some of the healthy cells in your body, this can cause side effects. Most side effects will go away after treatment finishes. 

Booklets and resources

Why am I having chemotherapy?

Having chemotherapy depends on different factors. These include:

You may have chemotherapy for one of the following reasons:

  • As a main treatment for cancers such as lymphomas and leukaemias
  • To shrink a cancer before surgery or radiotherapy.(neo-adjuvant chemotherapy)
  • To reduce the risk of cancer coming back after surgery or radiotherapy (adjuvant chemotherapy)
  • To make radiotherapy work better (chemoradiation)
  • To treat locally advanced or advanced cancer (palliative chemotherapy)
  • To shrink or control a cancer and relieve symptoms (palliative chemotherapy)

Your cancer doctor or chemotherapy specialist nurse will explain why chemotherapy is being advised for you.

Which chemotherapy drug will I have?

Not all cancers are treated with the same chemotherapy drugs. Different drugs affect the cancer cells in different ways. The drugs you are given and the way they are given will depend on the type of cancer you have.

You may have one chemotherapy drug or a combination of different drugs. When a combination of drugs is used, each drug is chosen for its different effects.

There are many different chemotherapy drugs and new drugs are being developed all the time. You may be invited to take part in a clinical trial.

Other anti-cancer drugs are used to treat cancer. For example, drugs called targeted therapies are directed at certain parts of the cancer cell and work differently to chemotherapy. These drugs can be given on their own or in combination with chemotherapy drugs.

You can search for information about a chemotherapy drug or combination of drugs on our Treatments and drugs A to Z page.

Planning your chemotherapy

Your treatment is planned by a cancer doctor. This doctor is an expert in treating people with chemotherapy, and other cancer treatments and drugs. You may also see a chemotherapy specialist nurse or a pharmacist.

They will tell you:

  • the aims of the chemotherapy
  • how it is given
  • how often you have chemotherapy and how long your course will take
  • any possible side effects.

How often you have chemotherapy, how it is given, and how long your course takes depends on:

Chemotherapy cycles

Chemotherapy is usually given as several sessions of treatment, with rest periods in between the sessions. The rest period allows your body to recover from the side effects. It also allows the number of healthy cells in your blood to go back to normal.

Chemotherapy and the rest period make up a cycle of your treatment. Your cancer doctor will explain the number of cycles you need to treat the cancer.

After your first cycle, you will have a better idea of what to expect. The complete course of all the cycles of chemotherapy you need may take several months.

Continuous or daily chemotherapy

Chemotherapy is sometimes given continuously by an infusion pump for several days or several weeks. If you are having chemotherapy as tablets or capsules, you may have them daily for several weeks or months before a rest period.

Preparing for chemotherapy

Having information about the chemotherapy treatment and its side effects can help you get organised and feel more in control. There are things you can do to help you feel prepared.

  • Your fertility

    Some chemotherapy drugs affect your fertility (the ability to get pregnant or make someone pregnant). If this is a concern for you, it is very important to talk to your cancer doctor before treatment starts. Sometimes your fertility can be preserved by storing sperm or storing eggs before chemotherapy begins.

  • Getting a wig

    If the chemotherapy drugs cause hair loss or thinning you might decide to have a wig fitted. You can have the wig fitted before your hair falls out. We have more information about wigs for cancer treatment.

  • Dental checks

    Your doctor or nurse may advise you to have a dental check-up before starting chemotherapy. If your teeth or dentures are in good condition, this reduces the risk of problems with your mouth during treatment.

  • Coronavirus (covid) swab test

    You may need to have a test to check for coronavirus before each treatment. The test is called a covid swab test.

  • Taking other drugs, vitamins or supplements

    Always tell your cancer doctor about any prescription and other drugs, vitamins, herbal remedies or supplements you are taking or plan to take. Some drugs may interact with chemotherapy drugs or make treatment less effective.

  • Vaccinations

    Vaccinations can reduce your risk of getting certain infections. Your doctor or nurse may talk to you about having vaccinations. Doctors usually recommend that people with cancer have a flu vaccination and a coronavirus vaccination.

    Vaccines can be given before, during or after cancer treatment. You can talk to your healthcare team about possibly getting a coronavirus vaccine before chemotherapy treatment starts. This may improve the vaccine’s effectiveness. But some people may need to start treatment before having the vaccine.

  • Work or education

    Before starting chemotherapy, it is a good idea to think about your work or education. This means you can make arrangements for time off during treatment.

  • Help at home

    Chemotherapy makes you tired, so you may need help with day-to-day tasks. Although you may find it hard to ask, family and friends often want to help. If you live alone or are caring for someone else, you can ask to talk to the hospital social worker about getting help.

  • Help with children

    If you have children, you may need help with taking and collecting them from school or clubs. Family and friends usually want to help, so accept their offers or ask for any help you need. It is also useful to know who you can contact at short notice to look after your children. We have more information about childcare when you have cancer.

Tests and scans

Your cancer doctor or specialist nurse will talk to you about any tests, scans or check-ups you need before chemotherapy begins.

  • Scans and x-rays

    Some chemotherapy drugs can affect organs, such as the heart or the kidneys. You may need tests to measure how well these organs are working before you have chemotherapy. For example, if you are having drugs that can affect the heart, you may have an electrocardiogram (ECG). This measures how well your heart is working. Or you may have an echocardiogram (ECHO), which uses soundwaves to create a picture of the heart. We have more information about heart tests.

    Some people may need further scans or x-rays to find out more about the extent of the cancer (its stage) before chemotherapy. We have more information about tests and scans.

  • Height and weight

    A nurse will check your height and weight. Your cancer doctor and pharmacist use this information to work out the right dose of chemotherapy for you.

  • Blood tests

    You will have a blood test before each cycle of chemotherapy. Sometimes your blood may be checked 1 to 2 days before chemotherapy. This can be done:

    • at the hospital where you are having chemotherapy
    • at your GP surgery or with a practice nurse
    • at a hospital closer to your home.

    The results will be ready for you when you go to have your chemotherapy.

  • Pregnancy test

    You may have a pregnancy test before starting treatment.

How will I have chemotherapy?

Chemotherapy can be given in different ways depending on the type of cancer you have and your treatment plan. Your chemotherapy nurse will explain what is involved.

Usually chemotherapy is given in a chemotherapy day unit or outpatient clinic. But depending on the type of chemotherapy, some people may stay in hospital for chemotherapy and some may have it at home.

Chemotherapy can be given:

  • by injection or a drip directly into a vein (intravenous chemotherapy)
  • by mouth as tablets or capsules (oral chemotherapy)
  • by injection into a muscle (intramuscular) or under the skin (subcutaneous)
  • by injection into the fluid around the spine and brain (intrathecal chemotherapy)
  • directly into a body cavity (intracavitary), for example the bladder
  • directly to the skin as a cream for some skin cancers.

Sometimes treatment involves having chemotherapy in more than one way. For example, you may have chemotherapy into a vein and also take chemotherapy tablets.

We have more information about how chemotherapy is given.

You can use our form to record details about your chemotherapy treatment.

Changes to your chemotherapy treatment plan

If your chemotherapy treatment plan needs to be changed, your cancer doctor or nurse will explain why.

It may be because of the effects of the chemotherapy on your body, or the effects on the cancer. Sometimes changes can be made to suit your personal circumstances. Depending on the reason, your doctor may:

  • delay your chemotherapy for a short while
  • reduce the dose
  • give you a different chemotherapy drug.

Effects on your body

The most common reason for delaying chemotherapy is a low number of white blood cells (neutrophils). This is not unusual. When your white blood cells are back to a healthy level, you can start your next cycle of chemotherapy.

Chemotherapy can also affect organs, such as the bone marrow, lungs, heart, kidneys and liver. You will have regular tests to monitor this. Some drugs can affect the nerves in your feet and hands. This is called peripheral neuropathy). Other drugs may affect your hearing.

Sometimes your doctor may need to reduce the dose of the drug or change your chemotherapy drug to a different one.

Effects on the cancer

Your doctor may arrange x-rays, scans, blood tests or a physical examination during treatment. This is to check the effects of chemotherapy on the cancer.

  • Physical examination

    If your doctor can see or feel the cancer, they will be able to tell if it is responding to chemotherapy by doing a physical examination.

  • Scans

    If the cancer can be seen on a scan, you may have a scan after a few cycles of chemotherapy. This is done to see if the cancer is getting smaller. Chemotherapy to reduce the risk of cancer coming back after surgery (adjuvant chemotherapy) will not usually need scans to check if it is working.

  • Blood tests

    With some cancers, blood tests can be used to check if treatment is working. These cancers release proteins into the blood (tumour markers) that can be measured with a blood test. If the tumour markers are reducing, it usually means the chemotherapy is working.

Personal reasons

You may also be able to delay chemotherapy if you have a special occasion coming up. Depending on the type of cancer, a small delay in your treatment is not usually a problem. Your cancer doctor or specialist nurse can tell you if this would be okay.

Side effects of chemotherapy

Chemotherapy treatment can cause different side effects. These will depend on the chemotherapy drugs you are having. Some side effects are more common than others, but you will not have them all.

Healthy cells in certain parts of the body are more sensitive to chemotherapy drugs. This includes cells in the bone marrow, which makes blood cells, and the digestive system.

This is why certain side effects are more common, such as being at risk of infection or feeling sick.

We have more information about the possible side effects of chemotherapy.

How chemotherapy may affect your everyday life

Many different areas of your life can be affected by having chemotherapy. You might find you go through many different emotions. You might also find you need to take a break from work, and need support with your finances.

You might have very few changes to your daily life but this depends on the type of chemotherapy you are having.

Even if you feel unwell after a cycle of chemotherapy, you may recover quickly. You may have time to do the things you usually do before your next cycle. If you have symptoms caused by the cancer, your chemotherapy may make you feel better by relieving them.

Chemotherapy can affect different areas of your life, such as:

  • Social life

    Depending on how you feel, there is no reason to stop going out or visiting friends if you plan ahead. If you are going out for the evening, try to rest during the day so you have more energy at night. If you are going out for a meal, take anti-sickness tablets, if you need to, before you go.

  • Alcohol

    For most people, having an occasional drink should not affect your chemotherapy treatment. But it is best to check with your cancer doctor or specialist nurse first.

  • Vaccinations

    Vaccinations can reduce your chance of getting certain infections. If you have had chemotherapy, you may not be able to have some vaccinations as your immune system may be weakened. These include live vaccinations, which use tiny amounts of a live virus or bacteria. Doctors usually recommend that you have a flu vaccination and a coronavirus vaccination. These are both inactivated vaccines, which help reduce the risk of infection. People with weak immune systems can have this type of vaccination. Before going abroad, ask your doctor if you need any vaccines and whether it is safe for you to have them.

  • Travel insurance

    Sometimes people who have cancer can find it difficult to get travel insurance. It is best to look for travel insurance as early as possible. If you are planning a holiday it is important to speak to your cancer doctor or nurse before you make any plans.

Late effects of chemotherapy

Some people may have late effects from chemotherapy. These are side effects that do not go away, or that develop months or years after treatment. Late effects may be minor and may not affect your daily life. Or, they may be more difficult to live with.

There are usually things that can help you cope with them. Some late effects improve over time and may eventually go away on their own.

Your follow-up after chemotherapy

After your treatment has finished, you will have regular check-ups and possibly scans or x-rays. This will depend on the type of cancer and the treatments you have had.

Many people find they get very anxious before their appointments. This is natural. It may help to get support from family, friends or from our cancer support specialists on 0808 808 00 00. Or visit our chemotherapy forum to talk with people who have had chemotherapy.

Follow-up appointments are a good opportunity to discuss any problems or worries you have. It may help to make a list of questions before you go so you do not forget anything important.

If you have any problems, or notice any new symptoms in between your appointments, let your GP, specialist nurse or cancer doctor know as soon as possible. Do not wait until your next scheduled appointment – you can ask for an earlier one.

You may have your follow-up appointments at a nurse-led clinic and only see your cancer specialist if something needs to be checked further. Instead of routine appointments, you may be asked to contact your nurse or cancer specialist if there is anything you are worried about. 

Getting support

Macmillan is here to support you. If you would like to talk, you can:

Beginning to recover after chemotherapy

You may have mixed emotions when you get to the end of your chemotherapy treatment. You will probably feel relieved, but you may also feel anxious and uncertain.

You might feel ready to get on with your life after chemotherapy, but sometimes you may feel less positive.

It is important to accept that it will take you time to recover and you may feel tired for a while. You may also have new challenges to cope with, such as physical effects caused by the cancer or its treatment. It usually takes time to adjust to these and find out what is now normal for you. Complementary therapies might help you feel better and reduce some stress and anxiety.

When your treatment is over, you may want to think about making some positive changes to your lifestyle. Many people find that over time they settle back into their usual routines. But it is important to remember that support is available to help you with any physical or emotional problems you have.

Get this information in another language or format

We are committed to making our website as accessible as possible, to make sure that everyone can use it.

We have information about chemotherapy in over 16 languages, and in other formats including audiobooks, and easy read.

If we don't have what you are looking for, you can ask for information to be translated for free or provided in a format to suit you. Email us at cancerinformationteam@macmillan.org.uk or call us on 0808 808 00 00.

Information about coronavirus (covid)

We understand that people are worried about coronavirus (COVID-19). You may have questions about the different vaccines, or you may be worried about how the pandemic will affect your cancer treatment. We have detailed information about coronavirus and cancer treatment here.

Talk to an expert

We know cancer throws a lot your way, and right now, the coronavirus pandemic is making it even tougher. If you're worried about something, and you need to talk to someone, whatever is on your mind, we're here to listen.

To speak to our experts, you can:

About our information

  • References

    Below is a sample of the sources used in our chemotherapy information. If you would like more information about the sources we use, please contact us at cancerinformationteam@macmillan.org.uk

    Brighton, D. Wood, M. The Royal Marsden Hospital Handbook of Cancer Chemotherapy. Elsevier Churchill Livingstone. 2005.

    National Institute for Health and Care Excellence (NICE) Neutropenic Sepsis Guideline CG151. 2012.

    Perry, MC. The Chemotherapy Source Book (5th ed.) Philadelphia: Lippincott, Williams & Wilkins. 2012.

    UKONS Acute Oncology Initial Management Guidelines Version 3, March 2018. Available from www.ukons.org (accessed June 2021).

  • Reviewers

    This information has been written, revised and edited by Macmillan Cancer Support’s Cancer Information Development team. It has been reviewed by expert medical and health professionals and people living with cancer. It has been approved by Chief Medical Editor, Professor Tim Iveson, Consultant Medical Oncologist.

    Our cancer information has been awarded the PIF TICK. Created by the Patient Information Forum, this quality mark shows we meet PIF’s 10 criteria for trustworthy health information.

The language we use

We want everyone affected by cancer to feel our information is written for them.

We want our information to be as clear as possible. To do this, we try to:

  • use plain English
  • explain medical words
  • use short sentences
  • use illustrations to explain text
  • structure the information clearly
  • make sure important points are clear.

We use gender-inclusive language and talk to our readers as ‘you’ so that everyone feels included. Where clinically necessary we use the terms ‘men’ and ‘women’ or ‘male’ and ‘female’. For example, we do so when talking about parts of the body or mentioning statistics or research about who is affected.

You can read more about how we produce our information here.

Date reviewed

Reviewed: 01 March 2022
Next review: 01 March 2025
Trusted Information Creator - Patient Information Forum
Trusted Information Creator - Patient Information Forum

Our cancer information meets the PIF TICK quality mark.

This means it is easy to use, up-to-date and based on the latest evidence. Learn more about how we produce our information.