Chlorambucil is a type of chemotherapy drug. It's pronounced klor-am-bu-sil.

It is used to treat:

  • chronic lymphocytic leukaemia (CLL)
  • Non-Hodgkin lymphoma
  • Hodgkin lymphoma

How does chlorambucil work?

Chlorambucil is one of a group of drugs called alkylating agents, which is a type of chemotherapy. Alkylating agents stop cells from reproducing by damaging cell DNA. DNA is the genetic code that is inside every cell in the body. It controls everything the cell does. If the DNA is damaged by chlorambucil the cancer cells cannot grow.  

How do you have chlorambucil?

Chlorambucil is a tablet. You should swallow the tablets whole with plenty of water and you take the tablets on an empty stomach. This means you take your tablet at least one hour before food or 3 hours after eating. You must not break, crush or chew the tablets.

You must take tablets according to the instructions your doctor or pharmacist gives you.

Whether you have a full or empty stomach can affect how much of a drug gets into your bloodstream.

You should take the right dose, not more or less.

Talk to your healthcare team before you stop taking or miss a dose of a cancer drug.

How often do you have chlorambucil?

Chlorambucil is sometimes given in combination with other chemotherapy drugs, targeted cancer treatments Open a glossary item, or with steroids. Or you might have chlorambucil on its own. You might take chlorambucil only on certain days as part of a treatment cycle Open a glossary item

How much chlorambucil you have and how often depends on the type of cancer you have and your treatment plan. 


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 chlorambucil?

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 (more than 10%). You might have one or more of them. They include:

Increased risk of getting an 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. 

Bruising, bleeding gums, and nosebleed

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).

Low levels of red blood cells (anaemia)

Red blood cells contain haemoglobin which carries oxygen around the body. Anaemia is when the level of haemoglobin in your blood is low. If you are anaemic you can feel very tired, dizzy, or lightheaded. You might also become breathless. Let your healthcare team know if you have these symptoms.

Occasional side effects

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

  • diarrhoea
  • feeling sick or being sick
  • mouth ulcers
  • a second cancer especially after long term use

Rare side effects

These side effects happen in fewer than 1 in 100 people (fewer than 1%). You might have one or more of them. They include:

  • severe skin rash, signs include fever, skin pain, blisters on the skin, eyes, and in your mouth and nose, and peeling of your skin. Your eyes may be sensitive to light. Contact your advice line or doctor straight away if you have any of these symptoms 
  • allergic reaction causing hives (a raised itchy rash under the skin)
  • fits (convulsions)
  • liver damage that could lead to yellowing of the skin and eyes (jaundice)
  • high temperature (fever)
  • problems with your bone marrow that do not get better. Symptoms include extreme tiredness (fatigue), fast or irregular heartbeat, pale looking skin (bone marrow failure)
  • lung problems, including scarring and thickening of the lungs. Symptoms include shortness of breath, difficulty breathing, and a dry cough
  • pain when having a pee. Drink plenty of fluids and tell your doctor, nurse, or pharmacist if you have this symptom
  • unusual shaking or twitching movements in your body that is not due to fits 
  • numbness or tingling in fingers or toes, speak to your healthcare team if you're finding it difficult to walk or complete fiddly tasks such as doing up buttons 

Coping with side effects

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

What else do I need to know?

Other medicines foods and drink

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 father a child after treatment with chlorambucil. 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.

Pregnancy and contraception

This treatment might harm a baby developing in the womb. It is important not to become pregnant or get someone pregnant while you're having treatment and for a few months afterwards.

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 because the drug may come through into 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