Chlorambucil (Leukeran®)

This information is about chlorambucil a chemotherapy drug used to treat different cancers, including chronic lymphocytic leukaemia (CLL), lymphoma and Waldenstrom's macroglobulinaemia.

Chlorambucil is usually given as tablets. You usually have it as an outpatient. Your cancer doctor or nurse will tell you how often you will have it.

Like all chemotherapy drugs chlorambucil can cause side effects, some of which can be serious so it’s important that you read the detailed information below. How chemotherapy affects people varies from person to person. It’s important to read about the side effects so that you know what to expect. Your healthcare team can talk to you more about this and give you advice on how to manage any side effects. Our more detailed information on chemotherapy may also be helpful.

Tell your doctor or nurse straight away if you have a temperature, feel unwell or have severe side effects, including any we don’t mention here. And if you need to go into hospital for any reason other than cancer, always tell the doctors and nurses that you are having chemotherapy.

What is Chlorambucil?

Chlorambucil (Leukeran®) is a chemotherapy drug used to treat different cancers including chronic lymphocytic leukaemia (CLL), low-grade non-Hodgkin lymphoma, Hodgkin lymphoma and Waldenstrom's macroglobulinaemia.

This information should ideally be read with our general information about chemotherapy and the type of cancer you have.

How chlorambucil is given

You usually have chlorambucil as an outpatient. During treatment you will see a cancer doctor, a chemotherapy nurse or a specialist nurse in the outpatient clinic. This is who we mean when we mention doctor or nurse in this information.

Before or on the day of treatment, a nurse or person trained to take blood (phlebotomist) will take a blood sample from you. This is to check that it is okay for you to have chemotherapy.

You will also see a doctor or nurse before you have chemotherapy. They will ask you how you have been. If your blood results are alright on the day of your treatment, the pharmacist will prepare your chemotherapy. Your nurse will tell you when your treatment is likely to be ready.

Taking your chemotherapy tablets

Chlorambucil is taken as tablets. The nurse or pharmacist gives you the tablets to take when you are at home. Always take your tablets exactly as explained. This is important to make sure they work as well as possible for you. They will also give you anti-sickness (anti-emetic) drugs to take.

The tablets are taken once a day. Swallow them whole with a glass of water. The tablets should be taken on an empty stomach – either one hour before food or three hours after.

If you are sick just after taking the tablets, contact the hospital. You may need to take another dose. If you forget to take a tablet, do not take a double dose. Keep to your regular schedule and let your doctor or nurse know

When taking your tablets, remember to:

  • keep them in the original package in the fridge
  • keep them safe and out of the reach of children
  • return any remaining tablets to the pharmacist if your treatment is stopped.

Your course of chlorambucil

You have chemotherapy as a course of several sessions (or cycles) over a few months. Each cycle normally takes 28 days (four weeks). You normally take your tablets for a specific number of days within each cycle, for example seven days or 14 days. Sometimes you may take a low dose every day.

Chlorambucil can be given on its own or in combination with other chemotherapy drugs. This will depend on the type of cancer you have.

Your doctor or nurse will tell you more about how long you need to take it for, and the number of cycles you are likely to have.

Possible side effects of chlorambucil

We explain the most common side effects of chlorambucil here. We don’t include all the rare ones that are unlikely to affect you.

You may get some of the side effects we mention but you are very unlikely to get all of them. If you are having other chemotherapy drugs as well, you may have some side effects that we don’t list here. Always tell your doctor or nurse about the side effects you have.

Your doctor can prescribe drugs to help control some side effects. It is very important to take them exactly as explained. They will be more likely to work better for you. Your nurse will give you advice about managing your side effects. After your treatment is over, the side effects will start to improve.

Serious and life threatening side effects

Sometimes cancer drugs can result in very serious side effects, which rarely may be life threatening. Your cancer doctor and nurse can explain the risk of these side effects to you.

Contact the hospital

Your nurse will give you telephone numbers for the hospital. You can call them if you feel unwell or need advice any time of day or night. Save these numbers in your phone or keep them somewhere safe.

More information about this drug

We are not able to list every side effect for this treatment here, particularly the rarer ones. For more detailed information you can visit the electronic Medicines Compendium (eMC).

Risk of infection

Chemotherapy can reduce the number of white cells in your blood. This will make you more likely to get an infection. When the number of white blood cells is low, it’s called neutropenia.

Contact the hospital straight away on the contact number you’ve been given 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.

Usually, the number of white blood cells will steadily increase and return to normal before your next treatment. You will have a blood test before having more chemotherapy. If your white blood cells are still low, your doctor may delay your treatment for a short time.

Bruising and bleeding

Chlorambucil can reduce the number of platelets in your blood. Platelets are cells that help the blood to clot. Tell your doctor if you have any bruising or bleeding you can’t explain.

Bruising and bleeding includes:

  • nosebleeds
  • bleeding gums
  • blood spots
  • rashes on the skin.

Some people may need a drip to give them extra platelets.

Anaemia (low number of red blood cells)

Chlorambucil can reduce the number of red blood cells in your blood. These cells carry oxygen around the body. If the number of red blood cells is low, you may be tired and breathless. Tell your doctor or nurse if you feel like this. If you are very anaemic, you may need a drip to give you extra red cells (blood transfusion).

Feeling sick

You may feel sick in the first few days after chemotherapy. Your doctor will prescribe anti-sickness (anti-emetic) drugs to help prevent or control sickness. Take the drugs exactly as your nurse or pharmacist explains to you. It’s easier to prevent sickness than to treat it after it has started.

If you still feel sick or are vomiting, contact the hospital as soon as possible. They can give you advice and change the anti-sickness drug to one that works better for you.


Your doctor can prescribe drugs to control diarrhoea. Let them know if it is severe or if it doesn’t get better. Make sure you drink at least two litres (three and a half pints) of fluids every day if you have diarrhoea.

Sore mouth

Your mouth may become sore and you may get ulcers. This can make you more likely to get an infection in your mouth. Gently clean your teeth and/or dentures morning and night and after meals. Use a soft-bristled or children’s toothbrush. Your nurse might ask you to rinse your mouth regularly or use mouthwashes. It’s important to follow any advice you are given and to drink plenty of fluids.

Tell your nurse or doctor if you have any problems with your mouth. They can prescribe medicines to prevent or treat mouth infections and reduce any soreness.

Second cancer

Rarely, chlorambucil can increase the risk of developing a second blood cancer, years later. But the benefits of treatment usually far outweigh this risk. This is more likely when you are taking chlorambucil for a longer period of time. Your doctor can talk to you about this.

Less common side effects of chlorambucil

Skin changes

Chemotherapy may affect your skin. Your doctor or nurse can tell you what to expect. If your skin feels dry, try using an unperfumed moisturising cream every day. Chlorambucil can cause a rash, which may be itchy.

Rarely, the skin rash can get worse and cause skin peeling, blisters and a sore mouth. This is more likely when you are taking chlorambucil for a longer period of time. If this happens, contact the hospital straight away on the contact number you’ve been given.

Always tell your doctor or nurse about any skin changes. They can give you advice and may prescribe creams or medicines to help. Any changes to your skin are usually temporary and improve when treatment finishes.

Changes in the way the liver works

Chemotherapy may affect how your liver works. This is usually mild and goes back to normal after treatment. You will have blood tests to check how well your liver is working.

Effects on the nervous system

Chlorambucil can affect the nervous system. Rarely, chlorambucil can cause seizures (fits). Your doctor can prescribe drugs to prevent fits. They will explain more about this.

Effects on the lungs

Chlorambucil can cause changes to the lungs. Always tell your doctor if you:

  • are wheezing
  • have a cough
  • develop a fever
  • feel breathless.

You should also let them know if any existing breathing problems get worse. If necessary, they can arrange for you to have tests to check your lungs.

Other information about chlorambucil

Blood clot risk

Cancer increases the chances of a blood clot (thrombosis) and chemotherapy can add to this. A clot can cause symptoms such as:

  • pain
  • redness and swelling in a leg
  • breathlessness
  • chest pain.

Contact your doctor straight away if you have any of these symptoms. A blood clot is serious but your doctor can treat it with drugs that thin the blood. Your doctor or nurse can give you more information.

Other medicines

Some medicines can interact with chemotherapy or be harmful when you are having chemotherapy. This includes medicines you can buy in a shop or chemist. Tell your doctor about any medicines you are taking, including over-the-counter drugs, complementary therapies and herbal drugs.


Chlorambucil may affect your fertility (being able to get pregnant or father a child). If you are worried about this, you can talk to your doctor or nurse before treatment starts.

Changes to your periods

Chemotherapy can sometimes stop the ovaries working. You may not get a period every month and they may eventually stop. In some women, this is temporary, but for others it is permanent and they start the menopause.


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


If you have sex within 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.


Women are advised not to breastfeed during treatment and for a few months after. This is in case there is chemotherapy in their breast milk.

Medical and dental treatment

If you need to go into hospital for any reason other than cancer, always tell the doctors and nurses that you are having chemotherapy. Explain you are taking chemotherapy tablets that should not be stopped or restarted without advice from your cancer doctor. Give the doctors and nurses the contact details for your cancer doctor.

Talk to your cancer doctor or nurse if you think you need dental treatment. Always tell your dentist you are having chemotherapy.