Rituximab

Rituximab is used to treat lymphoma and chronic lymphocytic leukaemia (CLL). It may sometimes be used to treat other cancers.

What is rituximab?

Rituximab is used to treat lymphoma and chronic lymphocytic leukaemia (CLL). It may sometimes be used to treat other cancers.

Rituximab belongs to a group of targeted therapy drugs called monoclonal antibodies. It is best to read this information with our general information about targeted therapy and the type of cancer you have. 

Monoclonal antibodies target specific proteins (receptors) on the surface of cells. Rituximab targets a protein called CD20 found on the surface of white blood cells called B-lymphocytes (B-cells). 

Rituximab locks on to CD20. It then triggers the body’s immune system to attack the cells and destroy them. Rituximab destroys both abnormal and normal B-cells. Once treatment is over, the body can replace the normal B-cells.

Your doctor will talk to you about this treatment and its possible side effects before you agree (consent) to have treatment.

More information about this treatment

This information is correct at time of publishing. But sometimes the types of cancer this treatment is used for, or treatment side effects, may change between revision dates.

You can talk to your cancer team if you want more detailed information about this treatment. Or visit the electronic Medicines Compendium (eMC) website, which has patient information leaflets (PIL) for individual drugs.

How rituximab is given

You will be given rituximab at a day unit, as an outpatient, or during a stay in hospital. Rituximab can be given on its own or with other cancer drugs.

During treatment, you usually see a:

  • blood cancer doctor (haematologist)
  • cancer nurse or specialist nurse
  • specialist pharmacist. 

This is who we mean when we mention doctor, nurse or pharmacist in this information.

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

You will speak to a doctor, nurse or pharmacist before you have treatment. They will ask how you have been feeling. If your blood results are okay, the pharmacy team will prepare your targeted therapy. 

Rituximab can be given as a drip into a vein (intravenous infusion) or as an injection under the skin. You can only have rituximab as an injection if you have already had at least one treatment as an intravenous infusion. 

Rituximab into the vein can be given: 

  • through a short, thin tube the nurse puts into a vein in your arm or hand (cannula)
  • through a fine tube that goes under the skin of your chest and into a vein close by (central line)
  • through a fine tube that is put into a vein in your arm and goes up into a vein in your chest (PICC line).

If you are having rituximab into a vein, it will be given through a pump. This will give you the treatment over a set time. Rituximab as an injection is given over 5 minutes.

The first infusion will be given slowly because it can cause a reaction. Before treatment, you will be given medicines to help prevent or reduce any reaction. You may have the first infusion in hospital. 

After the first treatment, you can usually have rituximab in the day unit or outpatient department. You can also have it over shorter periods of time.

Your course of treatment

You usually have a course of several cycles of treatment over a few months. Your nurse, pharmacist or doctor will discuss your treatment plan with you.

About side effects

We explain the most common side effects of this treatment here. We also include some that are less common. 

You may get some of the side effects we mention, but you are unlikely to get all of them. And you may have some side effects, including rarer ones, that we have not listed here. 

Other cancer treatments may cause different side effects. If you are also having other cancer treatment, you may have other side effects.

Always tell your doctor, nurse or pharmacist about any side effects you have. They can give you: 

  • drugs to help control some side effects 
  • advice about managing side effects. 

It is important to take any drugs exactly as explained. This means they will be more likely to work for you.

Serious and life-threatening side effects

Some cancer treatments can cause serious side effects. Sometimes, these may be life-threatening. Your doctor, nurse or pharmacist can explain the risk of these side effects to you.

Contact the hospital

Your doctor, nurse or pharmacist will give you 24-hour contact numbers for the hospital. If you feel unwell or need advice, you can call at any time of the day or night. Save these numbers in your phone or keep them somewhere safe.

Hepatitis B reactivation

If you have had hepatitis B (a liver infection) in the past, rituximab can make it active again. Your doctor or nurse will talk to you about this and test you for hepatitis B.

If your test shows that you have had it in the past you may be given treatment to prevent it becoming active again.

If you have active hepatitis B, you will not have treatment with rituximab.

Side effects while treatment is being given

Some people may have side effects while they are being given this treatment or shortly after they have it:

Allergic reaction

Some people have an allergic reaction while having this treatment. The first infusion is the most likely to cause a reaction, so it is usually given more slowly than later treatments. Before treatment, you will have medicines to help prevent or reduce any reaction.

Signs of a reaction can include:

  • feeling hot or flushed
  • shivering
  • itching
  • a skin rash
  • feeling dizzy or sick
  • a headache
  • feeling breathless or wheezy
  • swelling of your face or mouth
  • pain in your back, tummy or chest.

Your nurse will check you for signs of a reaction during your infusion. If you feel unwell or have any of these signs, tell them straight away. If you do have a reaction, they can treat it quickly.

Sometimes a reaction happens a few hours after treatment. If you develop any of these signs or feel unwell after you get home, contact the hospital straight away on the 24-hour number.

Low blood pressure

Some people have low blood pressure while they are having rituximab. If you usually take medicine to lower your blood pressure, your doctor may ask you not to take it for 12 hours before having rituximab. Sometimes, rituximab can make your blood pressure go up. The nurse will check your blood pressure regularly.

Tumour pain

During the infusion, you may have mild pain in the parts of the body where you have cancer. You may be given painkillers to help with this.

Problems at the injection site

If you have rituximab as an injection, you may have some redness and swelling where it is given (injection site). Your nurse can give you advice on coping with this.

Common side effects

Risk of infection

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

An infection can be very serious when the number of white blood cells is low. It is important to get any infection treated as soon as possible. If you have any of the following symptoms, contact the hospital straight away on the 24-hour number:

  • a temperature above 37.5°C  
  • a temperature below 36°C 
  • you feel unwell, even with a normal temperature
  • you have symptoms of an infection.

Symptoms of an infection include:

  • feeling shivery and shaking
  • a sore throat
  • a cough 
  • breathlessness
  • diarrhoea
  • needing to pass urine (pee) often, or discomfort when you pass urine.

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

Your white blood cell count 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, until your cell count increases.

Anaemia (low number of red blood cells)

This treatment can reduce the number of red blood cells in your blood. Red blood cells carry oxygen around the body. If the number of red blood cells is low, this is called anaemia. You may feel:

  • very low in energy
  • breathless 
  • dizzy and light-headed. 

If you have these symptoms, contact the hospital straight away on the 24-hour number. You may need treatment for anaemia. If you are very anaemic, you may need a drip to give you extra red blood cells. This is called a blood transfusion.

Bruising and bleeding

This treatment can reduce the number of platelets in your blood. Platelets are cells that help the blood to clot.

If the number of platelets is low, you may bruise or bleed easily. You may have:

  • nosebleeds
  • bleeding gums
  • heavy periods
  • blood in your urine (pee) or stools (poo)
  • tiny red, brown or purple spots that may look like a rash – these spots can be harder to see if you have black or brown skin. 

If you have any unexplained bruising or bleeding, contact the hospital straight away on the 24-hour number. You may need a drip to give you extra platelets. This is called a platelet transfusion.

Feeling sick

Your doctor may give you anti-sickness drugs to help prevent or control sickness during your treatment. Take the drugs exactly as your nurse or pharmacist tells you. It is easier to prevent sickness than to treat it after it has started.

If you feel sick, take small sips of fluids often and eat small amounts regularly. It is important to drink enough fluids. If you continue to feel sick, or are sick (vomit) more than once in 24 hours, contact the hospital as soon as possible. They will give you advice. Your doctor or nurse may change the anti-sickness drug to one that works better for you.

Loss of appetite

This treatment can affect your appetite. Don’t worry if you do not eat much for 1 or 2 days. But if your appetite does not come back after a few days, or if you are losing weight, tell your doctor, nurse or pharmacist. They can give you advice. They may give you food or drink supplements. Or they may suggest changes to your diet or eating habits to help.

Raised blood sugar levels

This treatment can raise your blood sugar levels and increase the risk of diabetes. 

Signs of raised blood sugar include:

  • feeling thirsty
  • needing to pass urine (pee) more often than usual
  • feeling more tired than usual. 

Tell your doctor or nurse if you have these symptoms. They can do tests to check your blood sugar level and give you advice.

If you already have diabetes, your blood sugars may be higher than usual. You may need to check them more often, or make changes to your diabetic treatment. Your diabetic doctor or nurse will talk to you about how to manage this.

Constipation

This treatment can cause constipation. Constipation means that you are not able to pass stools (poo) as often as you normally do. It can become difficult or painful. Here are some tips that may help:

  • Drink at least 2 litres (3½ pints) of fluids each day.
  • Eat high-fibre foods, such as fruit, vegetables and wholemeal bread.
  • Do regular gentle exercise, like going for short walks.

If you have constipation, contact the hospital on the 24-hour number for advice. They can give you drugs called laxatives to help. 

If you have not been able to pass stools for over 2 days and are being sick, contact the 24-hour number straight away. 

Diarrhoea

This treatment may cause diarrhoea. Diarrhoea means passing more stools (poo) than is normal for you, or having watery or loose stools. You may also have stomach cramps. If you have a stoma, it may be more active than usual. 

If you are passing loose stools 3 or more times a day and this is not normal for you, contact the hospital as soon as possible on the 24-hour number. Follow the advice they give you about:

  • taking anti-diarrhoea medicines 
  • drinking enough fluids to keep you hydrated and to replace lost salts and minerals
  • any changes to your diet that might help. 

They might also ask you for a specimen of your stool to check for infection.

Skin changes

This treatment may affect your skin. It may cause a rash, which might be itchy. You may notice a numbness, tingling, pricking or burning feeling in 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.

Rarely, a much more serious skin condition can develop. You may have a skin rash which then blisters, and your skin can peel. You may also feel unwell with flu-like symptoms such as a high temperature and joint pain. If you have any of these symptoms, contact the hospital on the 24 hour number you were given straight away.

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

Hair loss

Your hair will get thinner. Or you may lose all the hair from your head. You may also lose your eyelashes and eyebrows, as well as other body hair. Hair loss usually starts after your first or second treatment.

If you want to cover up hair loss, there are different ways you can do this. Your nurse will give you information about coping with hair loss

Remember to protect your skin from the sun. Use suncream with a sun protection factor (SPF) of at least 30 on your scalp. Or cover up with a hat or scarf.

Hair loss is almost always temporary. Your hair will usually grow back after treatment ends.

Muscle or joint pain

You may get pain in your muscles or joints for a few days after treatment. If this happens, tell your doctor, nurse or pharmacist. They can give you painkillers and advice. They can also tell you if any of the painkillers you usually take are suitable. 

Tell them if the pain does not get better. Having warm baths and resting regularly may help. 

Eye problems

This treatment may make your eyes feel sore, red and itchy. This is called conjunctivitis. Your doctor will prescribe eye drops to help. It is important to use these as explained.

Always tell your doctor or nurse if you have eye pain or notice any change in your vision.

Mood and sleep changes

You may have some mood changes during this treatment. You may feel low, depressed or anxious. You may have trouble sleeping. Tell your doctor or nurse if you notice any changes.

Effects on the lungs

This treatment can cause changes to the lungs. Tell your doctor, nurse or pharmacist if you develop: 

  • a cough that does not go away
  • wheezing
  • breathlessness.

You should also tell them if any existing breathing problems get worse. You may have tests to check your lungs.

Fluid build-up

This treatment can cause a build-up of fluid in the body. This will slowly get better after treatment ends. Contact the hospital on the 24-hour number if you:

  • are gaining weight 
  • have swelling in your face, legs or ankles.

They can give you advice and treatment to help.

Less common side effects

Effects on the heart

This treatment can affect how the heart works. You may have tests to check how well your heart is working. These may be done before, during and after treatment.

If the treatment is causing heart problems, your doctor may change the type of treatment you are having.

Contact the hospital straight away on the 24-hour number if you have any of these symptoms during or after treatment:

  • breathlessness
  • dizziness
  • changes to your heartbeat
  • swollen feet and ankles.

Other conditions can cause these symptoms, but it is important to get them checked by a doctor. 

Always call 999 if you have:

  • chest pain, pressure, heaviness, tightness or squeezing across the chest
  • difficulty breathing.

Effects on the brain

Very rarely, this treatment can affect the brain. This can cause symptoms including:

  • drowsiness or confusion
  • memory problems
  • trouble speaking
  • problems with balance, moving, or walking
  • changes in eyesight

Contact the hospital straight away if you have any of these symptoms. If someone with you notices you have any of these symptoms, they should contact the hospital straight away.

It is important not to drive or operate machinery if you have any of these symptoms.

Tumour lysis syndrome (TLS)

Some people are at risk of developing a condition called tumour lysis syndrome (TLS) during this treatment. When treatment makes large numbers of cancer cells die and break down quickly, they release lots of waste products into the blood. This can affect how well the kidneys work. It may also cause problems with the heart rhythm.

TLS can be prevented. You will have regular blood tests to check for TLS. If you are at risk of TLS, you may have:

  • extra fluids through a drip
  • medicines such as rasburicase through a drip, or allopurinol as tablets.

Drinking at least 2 litres (3½ pints) of fluid a day will also help.

Hearing changes

This treatment may cause ear pain or hearing changes, including hearing loss. You may have ringing in the ears. This is called tinnitus. You may also become unable to hear some high-pitched sounds. Hearing changes usually get better after this treatment ends. But some can be permanent. Tell your doctor if you notice any changes in your hearing.

Changes to your taste

Some foods may taste different or have no taste. Try different foods to find out what tastes best to you. You may also get a bitter or metallic taste in your mouth. Your doctor, nurse or pharmacist can give you advice. It might help to try:

  • sucking sugar-free sour or boiled sweets
  • eating cold foods
  • eating sharp-tasting fresh fruit.

Taste changes usually get better after treatment ends. We have more information about coping with changes to taste.

Other information

Blood clot risk

Cancer and some cancer treatments can increase the risk of a blood clot. Contact the hospital straight away on the 24-hour number if you have any of these symptoms during or after treatment:

  • throbbing pain or swelling in a leg or arm
  • reddening of the skin in the area – if you have black or brown skin, this can be harder to notice, but the skin might become darker
  • suddenly feeling breathless or coughing.

Always call 999 if you have:

  • chest pain
  • difficulty breathing.

A blood clot is serious, but it can be treated with drugs called anticoagulants. These thin the blood. Your doctor, nurse or pharmacist can give you more information about preventing and treating blood clots.

Vaccinations

Doctors usually recommend that people with cancer have vaccinations for flu and for coronavirus (covid). These help reduce your risk of serious illness from these infections. Most people can have these vaccines, including people with weak immune systems.

If your immune system is weak, you should not have live vaccinations. Live vaccines can make you unwell because they contain a very weak version of the illness they will protect you against. Live vaccines include Zostavax®, which is a shingles vaccine, and the yellow fever vaccine.

It is important to ask your doctor, nurse or pharmacist for advice about having vaccinations. They can explain what vaccines are right for you and when it is best to have them.

Other medicines

Some medicines can affect how this treatment works or be harmful while you are having it. Always tell your cancer doctor, nurse or pharmacist about any drugs you are taking or planning to take, such as: 

Contraception

Your doctor, nurse or pharmacist will advise you not to get pregnant or make someone pregnant while having this treatment and for some time afterwards. The drugs may harm a developing baby. It is important to use contraception to prevent pregnancy. Follow their advice about:

  • what types of contraception to use 
  • how long after treatment you should continue to use contraception. 

Breastfeeding

You are advised not to breastfeed while having this treatment, or for some time after treatment ends. This is because the drugs could be passed to the baby through breast milk. 

Your doctor, nurse or pharmacist can give you more information.

Fertility

Some cancer drugs can affect whether you can get pregnant or make someone pregnant. If you are worried about this, it is important to talk with your doctor before you start treatment.

Medical and dental treatment

If you need medical treatment for any reason other than cancer, always tell the healthcare professional that you are having cancer treatment. Give them the contact details for your cancer doctor or cancer team so they can ask for advice.

If you have appointments with a dentist, always tell them you are having cancer treatment. Talk to your cancer team before you have any dental treatment.

About our information

  • Reviewers

    This information has been written, revised and edited by Macmillan Cancer Support’s Cancer Information Development team. It has been reviewed by expert health professionals and people living with cancer.

    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.

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

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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.

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Date reviewed

Reviewed: 01 July 2023
|
Next review: 01 July 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.