Why is this medication prescribed?
Vemurafenib is used to treat certain types of melanoma (a type of skin cancer) that cannot be treated with surgery or that has spread to other parts of the body. Vemurafenib is in a class of medications called kinase inhibitors. It works by blocking the action of an abnormal protein that signals cancer cells to multiply. This helps slow or stop the spread of cancer cells.
How should this medicine be used?
Vemurafenib comes as a tablet to take by mouth. It is usually taken with or without food twice a day, in the morning and evening, about 12 hours apart. Take vemurafenib at around the same times every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take vemurafenib exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor. Do not stop taking vemurafenib without talking to your doctor.
Swallow the tablets whole with a glass of water; do not chew or crush them.
Your doctor may decrease your dose of vemurafenib or tell you to stop taking vemurafenib for a period of time during your treatment. This depends on how well the medication works for you and the side effects you experience. Be sure to tell your doctor how you are feeling during your treatment with vemurafenib.
Your doctor or pharmacist will give you the manufacturer's patient information sheet (Medication Guide) when you begin treatment with vemurafenib and each time you refill your prescription. Read the information carefully and ask your doctor or pharmacist if you have any questions. You can also visit the Food and Drug Administration (FDA) website (http://www.fda.gov/Drugs/DrugSafety/ucm085729.htm) or the manufacturer's website to obtain the Medication Guide.
Other uses for this medicine
This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.
What special precautions should I follow?
Before taking vemurafenib,
- tell your doctor and pharmacist if you are allergic to vemurafenib, any other medications, or any of the ingredients in vemurafenib tablets. Ask your pharmacist or check the Medication Guide for a list of the ingredients.
- tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any of the following: certain antifungals such as itraconazole (Sporanox), ketoconazole (Nizoral), and voriconazole (Vfend); clarithromycin (Biaxin, in PrevPac); certain medications for human immunodeficiency virus (HIV) or acquired immunodeficiency syndrome (AIDS) such as atazanavir (Reyataz), indinavir (Crixivan), nelfinavir (Viracept), ritonavir (Norvir, in Kaletra), and saquinavir (Invirase); medications for irregular heartbeat such as amiodarone (Cordarone); certain medications for seizures such as carbamazepine (Carbatrol, Epitol, Tegretol), phenobarbital (Luminal), and phenytoin (Dilantin, Phenytek); nefazodone; rifabutin (Mycobutin); rifampin (Rifadin, in Rifamate, in Rifater, Rimactane); rifapentine (Priftin); telithromycin (Ketek); and warfarin (Coumadin, Jantoven). Your doctor may need to change the doses of your medications or monitor you carefully for side effects. Many other medications may also interact with vemurafenib, so be sure to tell your doctor about all the medications you are taking, even those that do not appear on this list.
- tell your doctor if you have or have ever had any type of skin cancer; a prolonged QT interval (a rare heart problem that may cause irregular heartbeat, fainting, or sudden death); a low level of calcium, magnesium, or potassium in your blood; heart, kidney, or liver disease.
- tell your doctor if you are pregnant or plan to become pregnant, or if you plan to father a child. You or your partner should not become pregnant while you are taking vemurafenib. You should use birth control to prevent pregnancy in yourself or your partner during your treatment with vemurafenib and for at least 2 months afterwards. Talk to your doctor about birth control methods that will work for you. If you or your partner becomes pregnant while taking vemurafenib, call your doctor. Vemurafenib may harm the fetus.
- tell your doctor if you are breast-feeding. You should not breast-feed while taking vemurafenib.
- if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking vemurafenib.
- plan to avoid unnecessary or prolonged exposure to sunlight and to wear protective clothing, sunglasses, lip balm and sunscreen (SPF 30 or higher). Vemurafenib may make your skin sensitive to sunlight.
What special dietary instructions should I follow?
Unless your doctor tells you otherwise, continue your normal diet.
What should I do if I forget a dose?
Take the missed dose as soon as you remember it. However, if it is within 4 hours of your next scheduled dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.
What side effects can this medication cause?
Vemurafenib may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- joint, muscle, arm, leg, or back pain
- swelling in hands, feet, ankles, or lower legs
- change in sense of taste
- hair loss
- dry or itchy skin
Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately:
- changes in skin appearance
- new wart
- skin sore or red bump that bleeds or does not heal
- change in size or color of a mole
- extreme tiredness
- unusual bruising or bleeding
- loss of appetite
- pain in the upper right part of the stomach
- yellowing of the skin or eyes
- eye sensitivity to light
- eye redness or pain
- blurred vision
If you experience any of the following symptoms of an allergic reaction or severe skin reaction, stop taking vemurafenib and call your doctor immediately or get emergency medical treatment:
- difficulty breathing or swallowing
- rapid, irregular, or pounding heartbeats
- rash or redness all over the body
- peeling or blistering skin
Vemurafenib may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.
If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).
What should I know about storage and disposal of this medication?
Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom). Throw away any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.
In case of emergency/overdose
In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.
What other information should I know?
Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests to check your body's response to vemurafenib. Your doctor will check your skin for any changes regularly during your treatment and for up to 6 months after treatment.
Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.
It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.