Before you begin taking a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should take this medication.
Abnormal heart rhythms: This medication can cause abnormal heart rhythms, which often have no symptoms. Certain medications (e.g., sotalol, quinidine, thioridazine, chlorpromazine, droperidol, pimozide, moxifloxacin, mefloquine, pentamidine, arsenic trioxide, probucol, tacrolimus) can increase the risk of a type of abnormal heart rhythm called QT prolongation, and should not be used in combination with sunitinib. You are more at risk for this type of abnormal heart rhythm and its complications if you:
- are female
- are older than 65 years of age
- have a family history of sudden cardiac death
- have a history of heart disease or abnormal heart rhythms
- have a slow heart rate
- have congenital prolongation of the QT interval
- have diabetes
- have had a stroke
- have low potassium, magnesium, or calcium levels
- have nutritional deficiencies
If you have heart disease and abnormal heart rhythms, or people are taking certain medications (e.g., verapamil, atazanavir), discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
Adrenal gland problems: Adrenal glands produce chemical messengers that are responsible for the normal function of the body’s organs, including how your body responds to injury or stress. On rare occasions, sunitinib may cause your adrenal gland to function improperly. Your doctor may monitor your adrenal gland condition especially if you have experienced stress such as surgery, injury, or severe infection.
Bleeding: Sunitinib may increase your risk of bleeding. On rare occasions, tumour bleeding has occurred. If you experience signs of bleeding (e.g., nosebleeds, darkened urine or stools), contact your doctor as soon as possible. Your doctor will perform regular blood tests to monitor you while you are taking this medication.
Blood cell counts: This medication may decrease the number of blood cells in your body. Your doctor will perform a blood test regularly to monitor your blood cell count while you are taking sunitinib.
Blood clots: Sunitinib may cause blood clots in the legs (deep vein thrombosis) to form that can move to the lungs (pulmonary embolism), heart (heart attack) or brain (stroke).
If you have a history of clotting you may be at increased risk of experiencing blood clot-related problems such as heart attack, stroke, or clots in the deep veins of your leg. Discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed. If you experience symptoms such as sharp pain and swelling in the leg, difficulty breathing, chest pain, blurred vision or difficulty speaking, seek immediate medical attention.
Blood glucose: Sunitinib can cause large decreases in glucose levels in the blood. This can happen even if you do not have diabetes. People with diabetes may find it necessary to monitor their blood sugar more frequently while using this medication. Changes to your medications may become necessary. If you experience symptoms of decreased blood sugar, such as cold sweats, cool, pale skin, headache, rapid heartbeat or unusual weakness, talk to your doctor. If you experience symptoms of dangerously low blood glucose, such as seizures, delirium, or loss of consciousness, this is a medical emergency and requires immediate medical attention.
High blood pressure: Your doctor may check your blood pressure before starting sunitinib and then ask you to measure your blood pressure regularly while taking sunitinib. Some people taking sunitinib develop very high blood pressure that requires adding blood pressure medications, changing the sunitinib dose, or even stopping the medication for a period of time. Talk to your doctor if you have any concerns.
Heart problems: This medication can decrease heart function, which may lead to heart failure. If you experience symptoms of heart failure such as unusual tiredness, shortness of breath, or swelling of the feet and ankles, contact your doctor.
If you have a history of decreased heart function (i.e., heart arrhythmias, congestive heart failure such as left ventricular dysfunction, heart attack, heart bypass surgery), discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
Jaw problems: On rare occasions, sunitinib may cause severe jaw problems, especially in people who have had invasive dental procedures or are taking bisphosphonates (e.g., alendronate, risedronate). If you experience any pain in the jaw, contact your doctor immediately. Invasive dental procedures should be avoided if possible.
Kidney function: This medication can cause decreased kidney function or kidney failure. If you experience puffy hands, face or feet, high blood pressure, unusual muscle cramping, or darkened urine, this medication may be affecting how well your kidneys are working. If you notice any of these symptoms, contact your doctor as soon as possible.
Liver function: This medication may cause a decrease in liver function. Sunitinib has also been reported to cause liver failure, which has in some cases caused death. If you experience symptoms of liver problems such as fatigue, feeling unwell, loss of appetite, nausea, yellowing of the skin or whites of the eyes, dark urine, pale stools, abdominal pain or swelling, and itchy skin, contact your doctor immediately.
Your doctor may want to test your liver function regularly with blood tests while you are taking this medication. This often allows reduced liver function to be identified before it becomes too severe.
Male contraception: Sunitinib can cause harm to the fetus if the female partner of a man taking sunitinib becomes pregnant. Men should use effective contraception while taking sunitinib.
Muscle problems: On rare occasions, people have had severe muscle problems while taking sunitinib. If you have muscle aches or weakness, or dark-coloured urine, contact your doctor as soon as possible.
Pancreatitis: Sunitinib can cause the pancreas to become inflamed. If you have a history of pancreatitis, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
Report signs of pancreatitis such as abdominal pain on the upper left side, back pain, nausea, fever, chills, rapid heartbeat, or swollen abdomen to your doctor immediately.
Reversible posterior leukoencephalopathy syndrome (RPLS): This is a rare disease of the brain that may occur when using medications like sunitinib. If you have had a previous episode of RPLS, sunitinib may not be an appropriate medication for you. Make sure your doctor knows you have experienced this before. If you experience signs and symptoms of RPLS, such as headache, seizures, change in awareness or consciousness, or vision changes, contact your doctor immediately.
Seizures: Rarely, there have been cases of people having seizures while taking sunitinib. If you have a history of seizures or seizure disorders, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
Thyroid problems: Sunitinib may decrease thyroid hormone levels. If you have symptoms of low thyroid such as dry skin, constipation, weight gain, or fatigue, go see your doctor.
Tumour lysis syndrome: Sunitinib, like many other cancer medications, causes many cancer cells to be suddenly killed when treatment is first started. This can overwhelm the body with waste products from the cells. As a result, the body may not be able to keep up with getting rid of all the waste. When this happens, you may experience nausea, shortness of breath, cloudy urine, or joint pain. This is called tumour lysis syndrome. Your doctor may prescribe some medications to help your body get rid of the waste products. Make sure you understand how to use these medications and report any of these signs or symptoms to your doctor immediately.
Pregnancy: This medication should not be used during pregnancy. If you become pregnant while taking this medication, contact your doctor immediately.
Breast-feeding: It is not known if sunitinib passes into breast milk. If you are a breast-feeding mother and are taking this medication, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.
Children: The safety and effectiveness of using this medication have not been established for children.