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Dabrafenib 850

Dabrafenib 850

This leaflet provides information on a course of treatment called dabrafenib.  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 dabrafenib are given at the end of the leaflet.

What is dabrafenib?

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

Why am I having dabrafenib?

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

How should I take the dabrafenib capsules?

Dabrafenib capsules should be taken twice a day with a glass of water. Do not mix with food or liquids other than water. Try to take the capsules 12 hours apart at approximately the same time each day.  Dabrafenib should be taken on an empty stomach.  That means at least one hour before food or at least two hours after eating. The capsules should be swallowed whole with a glass of water.  They must not be chewed or crushed. 

How many capsules will I need to take?

It is usual to have two capsules twice daily but this dose may be changed by your doctor.  The amount you need to take will be clearly marked on the boxes.  

What should I do if I forget to take my capsules?

  • If it’s within 6 hours of the normal time take them now.
  • If it’s more than 6 hours late do not take the capsules, please inform the doctor when next in clinic.

Do not take the extra tablets when your treatment should have finished.  It is important that even if you have missed any doses you should finish the treatment at the planned time.  

How should I store the dabrafenib 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 capsules should be returned to the hospital pharmacy or your local chemist for safe disposal.  

Can I bring relatives and friends with me? 

You are welcome to bring someone to stay with you during your treatment. Space is limited so there is not usually room for more than one person.  Treatment areas are not suitable for young children.

What are the possible side effects?

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

Hair loss

Unfortunately you may lose your hair or experience hair thinning with this treatment.  This is only temporary. If you do lose your hair, it will grow back when your treatment has finished.  

We have a leaflet that tells you more about coping with hair loss.  Please ask your nurse for a copy. 

Soreness to your hands and feet

You may experience mild pain, redness and swelling of your hands or feet.  If this occurs we recommend using a non perfumed cream or lotion regularly.  Please contact Velindre Cancer Centre if your hands or feet become painful. 

Sickness and loss of appetite 

You may experience a loss of appetite and some people may feel sick whilst taking dabrafenib but this can usually be well controlled with anti sickness medication.  If you are sick more than once in 24 hours despite taking regular anti-sickness medicine, you should stop taking your dabrafenib capsules and contact Velindre Cancer Centre for advice.  The telephone number is on page 8.


You may have diarrhoea with this treatment.  If this occurs it is important that you drink plenty of fluids.  Medication is available to control diarrhoea.  If you have four or more bowel movements in 24 hours above what is normal for you please contact Velindre Cancer Centre immediately.  The telephone number is on page 8. 

Tiredness and fatigue

Dabrafenib 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.

Skin changes

Dabrafenib may cause a rash or skin changes.  Some patients will develop new skin cancers called squamous cell carcinoma whilst being treated with dabrafenib.  This type of skin cancer is usually easily treated by removing it.  Your doctor will monitor you carefully but if you do notice any new skin blemishes please let your doctor know.  These skin cancers are not like melanomas and are NOT life threatening

Sore mouth

Your mouth may become sore or you may notice small ulcers. Your doctor may prescribe mouthwashes or medication to help with this. 

Some people find that their mouth is too sensitive for regular toothpaste.  If this happens try using mild children’s toothpaste.

If your mouth becomes very painful, or you are finding it difficult to eat and drink, you should stop taking your dabrafenib capsules and contact Velindre Cancer Centre for advice.  The telephone number is on page 8.

Myalgia (pain in the muscles)

Some patients may experience myalgia which is muscle or joint pain.  This can sometimes be severe but will only last for a few days.  If you already have painkillers at home you may find they relieve the pain.  If this does not work please contact Velindre Cancer Centre.  The telephone number is on page 8.  

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

Other side effects

Symptoms may include a temperature, fever and chills. However if you have any sign of an infection, such as pain when passing urine or passing urine more often, coughing green phlegm or chesty cough please see your local doctor.

Occasionally, dabrafenib may cause some heart problems.  If you have a heart condition or you take any heart medication, please tell your doctor before you start treatment.  

If you develop a dry cough or notice that you are short of breath please tell your doctor

Some people may experience problems with headaches.  Try taking the painkillers you would normally take for a headache.  If you find that painkillers do not help please tell your doctor or nurse.

Is it alright to take other medicines with dabrafenib?

If you are taking other medicines, vitamins or herbal remedies please let your doctor, nurse or pharmacist know. 

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.

Manufacturer’s patient information leaflets

Velindre leaflets provide information about very common and common side-effects: for more information regarding 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 attention at any time of the day or night. For example you should phone if you:

  • Are sick more than once in 24 hours
  • Have 4 or more bowel movements in 24 hours above what is normal for you
  • Have a very sore mouth 

Pharmacy department 029 2061 5888 ext 6223

Monday – Friday 9am – 5pm for queries about your medicines

Tenovus freephone 0808 808 1010

cancer helpline 


This leaflet 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.