Bevacizumab is used to treat various types of cancer and leukaemia. It is a ‘biologic’ medicine, that is, it is a manmade antibody that targets a specific protein on the surface of the cells that inhibits the formulation of blood vessels in tumours. This page from Great Ormond Street Hospital (GOSH) explains what bevacizumab is, how it is given and some of the possible side effects.

In the UK, bevacizumab is currently unlicensed for children and young people aged less than 18 years. Medicines are often used outside of their license (off-label) in children because clinical trial data is not available for a specific use. Prescribing medicines ‘off label’ is not necessarily hazardous but should be explained and agreed before use.

How is it given?

Bevacizumab is given as a slow infusion into a vein (intravenously or IV), through a cannula, central venous catheter or implantable port.

The initial dose will be given over 90 minutes, but next doses may be given more quickly (over 30 to 60 minutes) if it does not cause any side effects.

Effects on the unborn child

Bevacizumab must not be given to girls who may be pregnant or are likely to become pregnant in the near future. If your daughter is ten years old or older, we will ask her about her periods and any possibility that she could be pregnant. We will also carry out a pregnancy test on a fresh urine sample. If your daughter is sexually active, she must use a reliable form of contraception.

What are the side effects?

Altered blood counts

There will be a temporary reduction in how well your child’s bone marrow works. This means they may become anaemic (reduced blood cells), bruise or bleed more easily than usual, and have a higher risk of infection.

Your child’s blood counts will be checked regularly to see how the bone marrow is working. Please tell your doctor if your child seems unusually tired, has bruising, bleeding, or any signs of infection, especially a high temperature.

Allergic reaction

Some people receiving bevacizumab have an allergic reaction to the medicine. This reaction may be mild to severe.


Signs of a severe allergic reaction include any of the above, as well as shortness of breath. If you are in hospital and your child shows signs of a severe allergic reaction, call a doctor or nurse immediately.

Raised blood pressure

Bevacizumab may cause an increase in blood pressure. This will be monitored closely with each dose and additional medicines to bring blood pressure back to a normal range may be suggested.

Leakage of protein in urine

This may develop alongside raised blood pressure. Urine will be checked for the presence of protein before and during treatment.

Delayed wound healing

Slow healing of wounds and skin problems have been reported with bevacizumab so treatment if surgery is needed, infusions will be stopped for a period of time either side of the operation depending on the intensity of the operation.

Development of fistulae

Fistulae (abnormal connections between organs) are more likely for people who have had previous gastrointestinal problems or have had radiotherapy.

Seizures and other neurological problems

This is a very rare side effect and will be monitored for frequently during treatment.

Effect on fertility

Bevacizumab can affect fertility in girls and women. Please talk to your doctor if you would like more information.

Interactions with other medicines



Alert card

We recommend that your child carries a biological therapy alert card at all times. This could be important if your child needs emergency treatment for any reason.

Chicken pox

If your child is on bevacizumab and has not had chickenpox but comes into contact with someone who has chicken pox or shingles (either face to face or longer than 15 minutes in the same room), you should report to your doctor immediately as your child may be at risk of developing a more severe form of the infection an may need special treatment. If your child gets chicken pox or shingles you should also report to your doctor immediately for antibiotics to be given. If you are unsure whether your child has had chicken pox prior to starting bevacizumab, their immunity should be checked with a simple blood test at that time and the result entered on the parent-held monitoring card.


Your doctor will advise you if your child should avoid immunisation during treatment. Your child should NOT have any live vaccinations such as MMR, oral polio, chicken pox or BCG while taking bevacizumab. Inactivated or killed vaccines such as influenza/flu, meningitis C, pneumococcal, hepatitis, Hib, tetanus, diphtheria, whooping cough/pertussis and the killed version of the polio immunisation are permitted if the patient is stable under treatment. If you have other children who need vaccines while your child is taking bevacizumab, they should have these as normal, but they should also receive the ‘killed’ or inactivated polio vaccine. If you have any questions about vaccines and immunisations, please ask your doctor.

Compiled by:
The Pharmacy team in collaboration with the Child and Family Information Group
Last review date:
October 2019