Cetuximab (Erbitux)

What is cetuximab?

Cetuximab is a type of targeted cancer drug called a monoclonal antibody. It is a treatment for people with advanced bowel cancer and head and neck cancers.

Depending on your cancer type, you might have cetuximab alongside other chemotherapy drugs or radiotherapy treatment. 

You pronounce cetuximab as se-tux-i-mab.

How does cetuximab work?

Cetuximab is a type of monoclonal antibody. Monoclonal antibodies (mAbs) are made in the laboratory. They seek out cancer cells by targeting particular proteins on their cell surface.

How do you have cetuximab?

You have cetuximab as a drip into your bloodstream. 

You might have treatment through a long plastic tube that goes into a large vein in your chest. The tube stays in place throughout the course of treatment. This can be a:

• central line

• PICC line

• portacath

How often do you have cetuximab?

You have cetuximab once a week or every 2 weeks, depending on your chemotherapy regimen. It takes about 2 hours the first time you have it. If you don’t have any problems, the following treatments take an hour.

How long you have cetuximab depends on your cancer type.

Tests

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 cetuximab?

Side effects can vary from person to person. They also depend on what other treatment you are having. 

When to contact your team

Your doctor, nurse, or pharmacist will go through the possible side effects. They will monitor you closely 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

We haven't listed all the side effects here. Talk to your healthcare team if you have any new symptoms that you think might be a side effect of your treatment.

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:

Low levels of magnesium in the blood

You might have low levels of magnesium in the body. This can cause muscular weakness and tremors. Your doctor will do regular blood tests to check for this. And give you magnesium if your levels become low.

Liver changes

You might have liver changes that are usually mild and unlikely to cause symptoms. They usually go back to normal when treatment finishes.

You have regular blood tests to check for any changes in the way your liver is working.

Mild allergic reaction

A reaction may happen during the infusion, causing dizziness, breathing difficulties, fever and chills. Your nurse will give you medicines beforehand to try to prevent a reaction. 

Skin reaction

More than 8 out of 10 patients (80%) are likely to have a skin reaction with this drug. The majority of these skin reactions are mild, and only about 15 out of 100 (15%) are serious.

Most of these side effects happen in the first 3 weeks of starting treatment and disappear once the treatment is finished.

These side effects include:

• acne

• itching

• dry skin

• scaling of the skin

• hair growth

• nail changes

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:

• loss of fluid in your body (dehydration)

• decrease in levels of calcium in the blood

• loss of appetite and weight loss

• inflammation of the eye which causes irritation and redness in the eye (conjunctivitis)

• headache

• loose or water stools (diarrhoea)

• feeling and being sick

• feeling tired

• severe allergic reaction which can cause breathing difficulties, fainting, blood pressure changes and itchy skin

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:

• a blood clot starting in the deep veins of your body (deep vein thrombosis, DVT) that could possibly travel to your lungs (pulmonary embolism). This could be life threatening if not treated quickly

• a blood clot starting in the lung (pulmonary embolism) which could be life threatening if not treated quickly

• inflammation of the eye lid or front part of the eye. The eye may appear red or swollen

• a severe skin reaction that may start as tender red patches which leads to peeling or blistering of the skin. You might also feel feverish and your eyes may be more sensitive to light. This is serious and could be life threatening

Coping with side effects

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

Read more about how to cope with side effects

What else do you need to know?

Other medicines, foods and drinks

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

It is not known whether this treatment affects ​fertility​ in people. Talk to your doctor before starting treatment if you think you may want to have a baby in the future.

Contraception and pregnancy

It is unknown whether treatment may or may not harm a baby developing in the womb. It is important not to become pregnant or get someone pregnant while you are having treatment. Let your team know straight away if you or your partner become pregnant while having treatment.

Talk to your doctor or nurse about effective contraception you can use during treatment. Ask how long you should use it before starting treatment and after treatment has finished.

Breastfeeding

Don’t breastfeed during this treatment and for 2 months afterwards. The drug may come through in the 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.

Immunisations

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, and yellow fever.

You can usually 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 a vaccine in relation to your cancer treatment.

Contact with others who have had immunisations 

You can be in contact with other people who have had live vaccines as injections. If someone has had a live vaccine by mouth or nasal spray there may be a small risk the vaccine virus can be passed onto you if your ​immune system​ is weakened.

Your healthcare team will let you know if you need to take any precautions if you are in close contact with someone who has had a live vaccine.

Read more about immunisations and cancer treatment

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.

eMC website

You can report any side effect you have to the Medicines and Healthcare products Regulatory Agency (MHRA) as part of their Yellow Card Scheme.

Report a side effect to the MHRA