Before you begin using 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 use this medication.
Abnormal heart rhythms: This medication can cause abnormal heart rhythms. Certain medications (e.g., sotalol, quinidine, 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 lenvatinib. 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 death due to heart attack or similar heart problems
- 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 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.
Birth control: Effective birth control should be practiced while using this medication. Males taking this medication should use a spermicide in addition to a barrier method of birth control (e.g., condoms). Women taking this medication must also use reliable birth control while taking lenvatinib and for at least 1 month after stopping the medication. The effectiveness of hormonal contraceptives, such as birth control pills has not been determined. Barrier methods of birth control are recommended.
Bleeding: Lenvatinib may cause a reduced number of platelets in the blood, which can make it difficult to stop cuts from bleeding. If you notice any signs of bleeding, such as frequent nosebleeds, unexplained bruising, or black and tarry stools, notify your doctor as soon as possible. Your doctor will order routine blood tests to make sure potential problems are caught early.
Blood clots: This medication may increase the chance of blood clot formation, causing reduction of blood flow to organs or the extremities.
If you have a history of clotting you may be at increased risk of experiencing blood clot-related problems such as heart attack, or stroke. 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. The safety of using this medication within 6 months of experiencing a blood clot has not been studied.
Gastrointestinal problems: Lenvatinib can cause perforation of the stomach or intestines. If you experience severe abdominal pain, fever, vomiting, or nausea, contact your doctor immediately.
Heart function: This medication may cause symptoms of heart failure. Contact your doctor as soon as possible if you develop symptoms of heart problems such as shortness of breath, chest pain, rapid heartbeat, or swollen ankles.
High blood pressure: Lenvatinib can cause increased blood pressure. If you have high blood pressure, 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.
Kidney function/failure: 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 is broken down by the liver. Liver disease or reduced liver function may cause this medication to build up in the body, causing side effects. If you have liver problems, 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. Your doctor may want to test your liver function regularly with blood tests while you are taking this medication.
Lenvatinib has been reported to cause a decrease in liver function, which has in rare cases caused liver failure. 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.
Reversible posterior leukoencephalopathy syndrome (RPLS): This is a rare disease of the brain that may occur when using medications like lenvatinib. If you experience signs and symptoms of RPLS, such as headache, seizures, change in awareness or consciousness or vision changes, contact your doctor immediately.
Surgery: This medication causes changes to the blood and any slow down the healing process for wounds. Make sure anyone involved in your medical care knows you are taking lenvatinib.
Thyroid function: This medication can affect the way the body uses thyroid hormones. If you take thyroid replacement medication, your doctor may need to adjust the dose while you are taking lenvatinib.
Pregnancy: Lenvatinib is likely to harm the developing baby if it is taken by the mother while she is pregnant. This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately.
Breast-feeding: It is not known if lenvatinib 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.
Seniors: People over the age of 65 years may be more at risk of side effects from this medication.