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Entrectinib A1254         

Information leaflet on entrectinib treatment A1254         

This leaflet provides information on a course of treatment called entrectinib.  The leaflet will explain what this is and when and how it is given.  It will also tell you about common side effects that you may experience.  Contact telephone numbers and details of how to obtain further information on entrectinib are given at the end of the leaflet.

Your ‘specialist team’ refers to your oncology team at Velindre Cancer Centre which includes doctors, specialist nurses and non-medical independent prescribers which may be a nurse or a pharmacist. 

What is entrectinib?

Entrectinib is an anti cancer drug.  It is not chemotherapy.  It works by slowing down or stopping the cancer’s growth.

Entrectinib is given as capsules which are usually taken daily.

Why am I having entrectinib?

Your doctor has prescribed entrectinib because it has been found to be effective in controlling your type of cancer.

How often will I see the specialist team?

You will be reviewed by your specialist team regularly.  You will either see your specialist team in clinic or you will speak to them virtually. 

You will have regular blood tests and we will check how you are feeling and discuss any problems you may have.  This is so we can check how entrectinib is affecting you.  If your blood results are satisfactory, your capsules will be prescribed

How should I take entrectinib?

Entrectinib capsules should be taken once a day with a glass of water. Try to take it at approximately the same time each day.  The capsules should be swallowed whole and must not be opened or dissolved since the contents of the capsule are very bitter. They can be taken with or without food but should not be taken with grapefruit or grapefruit juice. 

How many capsules will I need to take?

The amount you need to take will be clearly marked on the boxes.  If you take too many capsules, please ring the treatment helpline  immediately.  The telephone number is at the end of the leaflet.
What should I do if I miss a dose?
If you miss a dose, you can take the missed dose as long as it is within 12 hours of your normal time

How should I store the entrectinib capsules?

Your capsules should be stored in their original packaging in a safe place away from children.  They should be kept in a cool dry place.  Any unused medication should be returned to the hospital pharmacy or your local chemist for safe disposal.  

What are the possible side effects?

There are a number of possible side effects which can occur with entrectinib treatment.  The doctors, nurses and pharmacy team can give you advice or answer any questions you may have.

Serious side effects 

Please contact the treatment helpline if you notice any of the following. Your doctor may lower your dose, stop your treatment for a short time or stop your treatment completely: 

  • you have a cough, shortness of breath, and swelling in your legs or arms (fluid retention). 
  • you feel confused, have changes in mood, memory problems or hallucinations 
  • you feel dizzy or light-headed, or feel your heart beating irregularly or fast, 
  • you notice any joint pain, bone pain, deformities or changes in your ability to move 
  • you notice a significant change in the amount of urine you’re passing. We will monitor your bloods regularly as these tablets can affect your kidneys.  

Other side effects

•    Effects on your bowels.

This treatment has been known to cause either constipation or diarrhoea. If you experience constipation it is important that you increase the amount of fluids you drink.  You may need laxatives.

If you experience diarrhoea it is important that you drink plenty of fluids.  Medication is available to control diarrhoea.  If you have 4 or more bowel movements in 24 hours above what is normal for you please contact Velindre Cancer Centre immediately.  The telephone is at the end of the leaflet.

•    Nausea and vomiting

We will give you anti sickness tablets to take if you need them.  If you are sick more than once in 24 hours despite taking regular anti-sickness medicine, contact Velindre Cancer Centre for advice.  The telephone number is at the end of the leaflet. 

•    Skin reactions

Skin reactions are common with entrectinib.  You may develop a rash that is dry, itchy and causes mild discomfort.  For a small number of people this reaction may be more severe.  A severe rash would affect a large part of your body, may be painful and may become infected. 

To reduce the possibility of severe skin reactions we suggest that you:

  • use non-perfumed moisturising creams on your face and upper body from the start of your treatment 
  • avoid exposure to the sun, wear a hat and use a high factor sunscreen
  • don’t use hot water on your skin
  • don’t use soap if your skin is dry - use a soap alternative such as aqueous cream 
  • try not to rub your skin vigorously - pat gently dry 
  • wear comfortable clothes and shoes that do not rub

This skin reaction is temporary and will resolve completely after you have finished treatment.  If you develop a severe skin reaction which is causing you pain or stopping you carrying out your normal activities, please contact Velindre Cancer Centre for advice.  The telephone is at the end of this leaflet.

•    Tiredness and fatigue

Entrectinib treatment can make you feel more tired than usual.  It is important to listen to your body and rest if you need to, but carry out your normal activities if you feel able.  Some people find it beneficial to take gentle exercise as well as taking rest.

•    Low blood counts

Entrectinib can affect your blood count, occasionally, this may increase your risk of bleeding.  If you notice unusual bruising or bleeding, please contact Velindre Cancer Centre immediately for advice.  The telephone numbers are towards the end of the leaflet.

•    Infection

You are at an increased risk of picking up infections because your white blood cells which help fight infections may be reduced by this treatment.  

If you develop an infection whilst your white blood cells are low, you are at risk of sepsis, this can be life threatening. 

Contact Velindre Cancer Centre immediately if you develop any signs of infection, for example flu like symptoms or a temperature above 37.5°centigrade. The telephone number at the end of this leaflet.

•    Blood clots

A diagnosis of cancer can increase your risk of developing a blood clot (thrombosis), and having cancer treatment may increase this risk further.  It is important to tell your doctor immediately if you have symptoms such as pain, redness and swelling in your leg, or breathlessness and chest pain.  
Blood clots can be very serious.  However, most clots can usually be successfully treated with drugs to thin the blood.  Your doctor or nurse can give you more information.

Sometimes cancer drugs can have very serious side effects which rarely can be life threatening. It is important to inform Velindre cancer centre if you are concerned about any side-effects.

Can I drive whilst taking entrectinib?

Some people can feel very tired, slightly dizzy, have some blurred vision or feel confused when they first start taking entrectinib.  You should not drive if you experience any of these side effects.  If these persist or cause any problems please talk to your doctor or nurse. 

Pregnancy, Contraception and Breast Feeding

Women sometimes find that entrectinib treatment affects their periods.  They could become heavier, lighter or even stop altogether.  

It is important women do not become pregnant for at least 5 weeks after stopping treatment.  
It is important men do not father a child whilst having this treatment and until 3 months after stopping this treatment.  This is because entrectinib could damage the unborn baby. 

You should use another reliable method of birth control such as a barrier method (e.g. condom). 
Talk to your doctor about the right methods of contraception for you and your partner.

It is important not to breastfeed whilst taking the medication

Is it ok to take other medicines with entrectinib?

If you are taking other medicines, vitamins or herbal remedies please let your doctor, nurse or pharmacist know.  There are a few medications that you may have to avoid.  These include St John’s Wort, warfarin, fentanyl, statins and medications used to treat HIV, epilepsy, fungal infections amongst others. 

Manufacturer’s patient information leaflets

Velindre leaflets provide information about very common and commonly reported side-effects (we are unable to list all of the common side effects), for more information regarding these and the less common side-effects please refer to the manufacturers patient information leaflets, obtained from Velindre pharmacy and/or on the internet at Sometimes patients may find these leaflets difficult to read however. Please ask if you would like a copy from your doctor or from Velindre pharmacy

Contact telephone numbers

Velindre Cancer Centre 029 2061 5888
Ask for the treatment helpline if you are unwell at home and need immediate advice at any time of the day or night. 

Pharmacy department  029 2061 5888 ext 6223
Monday – Friday 9am – 5pm for queries about your medicines

Macmillan freephone Helpline 0808 808 0000

Tenovus freephone 0808 808 1010
cancer helpline 

Smokers helpline Wales on 0800 085 2219
This information is also available in Welsh

This leaflet was written by health professionals.  The information contained in this leaflet is evidence based.  It has been approved by a team of doctors, nurses and patients.  It is reviewed and updated every 2 years