Vemurafenib is used to treat a type of skin cancer (known as melanoma) that has spread to other parts of the body or which cannot be removed by surgery.
This medicine may also be used to treat Erdheim-Chester disease (a rare type of cancer characterised by excessive production of white blood cells, called histiocytes).
Vemurafenib is used specifically in individuals who carry a certain type of abnormal gene called BRAF.
Take Vemurafenib exactly as directed by your doctor or according to the instructions on the label. Do not take more or less than instructed by your doctor.
You may take this medicine with or without food. However, do not take it regularly on an empty stomach.
Try to take it at the same time each day.
Swallow the tablet whole with a glass of water. Do not crush or chew the tablet.
If you vomit after taking Vemurafenib, do not take an additional dose. Take the next dose at your usual scheduled time.
The dose of this medicine will be decided by your doctor. Your doctor will advise you on the treatment timeframe depending on your condition and response to the medication.
Vemurafenib must be taken regularly for it to be effective. Continue taking this medicine even when you feel better. Do not stop taking it unless instructed by the doctor.
If you miss a dose and it is 4 or more hours before the next dose is due, take the missed dose and return to your normal dosing schedule.
If it is less than 4 hours before the next dose is due, skip the missed dose and return to your normal dosing schedule.
DO NOT double a dose under any circumstances.
If you often forget to take your medicine, let your doctor and pharmacist know.
Inform your doctor if you have the following conditions:
- history of skin cancer
- pre-existing bone-marrow cancer
- electrolyte (e.g. sodium, potassium) abnormalities
- heart problems e.g. heart rhythm disorder
- kidney disease
- liver disease
Let your doctor know if you are pregnant or breastfeeding.
It is important that you do not get pregnant while taking this medicine. You must use proven birth control methods during Vemurafenib therapy and for at least 6 months after stopping the treatment. Birth control medicines containing hormones may not be effective. You may wish to discuss other reliable methods of birth control with your doctor.
Some genetic traits can affect an individual’s response to this medicine. Your doctor may perform genetic testing before giving you Vemurafenib to know if it is suitable for you.
If you have had or are going to have radiotherapy, inform your doctor that you are taking this medicine. Vemurafenib may worsen the side effects of radiation therapy.
Why is it important to keep my appointments with the doctor?
Keep your appointments with your doctor. Your doctor needs to monitor your condition and check your response to the medication regularly.
- Routine tests (e.g. liver, kidney or heart function, electrolyte levels, eye examination) may be done while you are being treated with this medicine. Your doctor will advise you about how often you will need to have these tests.
- Regular monitoring for signs and symptoms of skin lesions or any changes in your skin may also be needed.
Vemurafenib may cause tiredness or some problems with your eyesight, such as blurred vision. If affected, do not drive or take part in any activity in which you need to be alert or see clearly.
Other side effects include any of the following: headache, dizziness, diarrhoea, nausea, vomiting, constipation, change in taste, cough, weakness, back pain, joint and muscle pain, joint swelling, tingling or burning sensation in the hands and feet, loss of appetite, weight loss, hair loss, itching, and rash.
Some side effects may need immediate medical help. Alert your doctor quickly if you experience any of the following:
- rashes, breathlessness, swollen face, eyes, or mouth
- unusual thickening of the skin in the palm of the hand or in the sole of the feet with tightening of the fingers inward
- abnormal skin growths e.g. new warts, skin sores or reddish bump that bleeds or does not heal, changes in size or colour of mole
- yellowing of the skin or eyes, abdominal pain, dark coloured urine, swelling in the legs and ankles
- eye pain, redness of the eye, abnormal eye sensitivity to light
- light-headedness, feeling faint, dizziness, fast or irregular heartbeat
- rashes with peeling of the skin or blistering of the lips, mouth or eyes accompanied by fever
This medicine may also make your skin more sensitive to sunlight. Apply sunscreen when going outdoors and avoid prolonged exposure to sunlight and UV lamps.
Inform your doctor if any of these side effects do not go away or are severe, or if you experience other side effects.
Inform your doctor and pharmacist if you are taking any of these medicines:
- medicines for epilepsy (fits or seizures) e.g. phenytoin, carbamazepine
- medicines to treat fungal infection e.g. ketoconazole, itraconazole, voriconazole
- certain antibiotics e.g. clarithromycin, azithromycin, telithromycin
- medicines to treat TB (infection known as tuberculosis) e.g. rifampicin, rifabutin
- mizolastine (medicine for cold or allergy)
- tizanidine (muscle relaxant)
- ipilimumab (medicine for cancer)
- digoxin (medicine for heart disease)
- hydroxychloroquine (medicine for malaria)
- birth control pills
- St. John's wort (herbal medicine)
This list does not include all medicines that may interact with Vemurafenib.
Always notify your doctor and pharmacist if you are taking any other medicines, including herbal tonics such as traditional Chinese medicines, supplements and medicines that you buy without a prescription.
Avoid excessive consumption of grapefruit or grapefruit juice.
Store in a cool, dry place away from the reach of children. Protect from moisture.
Medicines must not be used past the expiry date.
As this is a cancer medicine, always return any unused or expired tablets to the clinic, hospital, or pharmacy for disposal. Do not throw it away in the household waste.