This information from Lexicomp® explains what you need to know about this medication, including what it’s used for, how to take it, its side effects, and when to call your healthcare provider.
- A type of abnormal heartbeat (prolonged QT interval) has happened with this drug. This can be life-threatening and may lead to another type of severe abnormal heartbeat (torsades de pointes). Call your doctor right away if you have a fast or abnormal heartbeat, dizziness, or if you pass out.
- Have your blood work checked and an ECG (to see how your heart beats) as you have been told by your doctor.
- Do not take this drug if you are taking certain other drugs, including any drugs that can raise the chance of a prolonged QT interval (a type of heartbeat that is not normal). There are many drugs that interact with this drug. Talk with your doctor and pharmacist to make sure it is safe to take this drug with all of your drugs.
- It is used to treat lung cancer.
- If you are allergic to this drug; any part of this drug; or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
- If you have electrolyte problems (like calcium, magnesium, potassium, sodium).
- If you are breast-feeding. Do not breast-feed while you take this drug and for 1 week after your last dose.
This is not a list of all drugs or health problems that interact with this drug.
Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take this drug with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.
- Tell all of your health care providers that you take this drug. This includes your doctors, nurses, pharmacists, and dentists.
- Heart problems like heart failure have happened in people taking this drug. Sometimes, this has been deadly. Call your doctor right away if you have chest pain or pressure, a heartbeat that does not feel normal, shortness of breath, a big weight gain, or swelling in the arms or legs.
- You will need to have heart function tests while taking this drug. Talk with the doctor.
- Diarrhea is common with this drug and can be severe. Call your doctor to find out what to do if you have diarrhea or stomach cramps. You will need to take care not to become dehydrated. Do not try to treat diarrhea without first checking with your doctor.
- Avoid grapefruit and grapefruit juice.
- If you are 65 or older, use this drug with care. You could have more side effects.
- This drug may affect fertility. Fertility problems may lead to not being able to get pregnant or father a child. If you plan to get pregnant or father a child, talk with your doctor before taking this drug.
- This drug may cause harm to an unborn baby. A pregnancy test will be done before you start this drug to show that you are NOT pregnant.
- If you may become pregnant, you must use a non-hormone type of birth control (like condoms) while taking this drug and for some time after the last dose. Ask your doctor how long to use birth control. If you get pregnant, call your doctor right away.
- If your sex partner may get pregnant, you must use birth control while taking this drug and for some time after the last dose. Ask your doctor how long to use birth control. If your partner gets pregnant, call the doctor right away.
WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:
- Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
- Signs of fluid and electrolyte problems like mood changes, confusion, muscle pain or weakness, fast or abnormal heartbeat, severe dizziness or passing out, increased thirst, seizures, feeling very tired or weak, decreased appetite, unable to pass urine or change in the amount of urine produced, dry mouth, dry eyes, or severe upset stomach or throwing up.
- Signs of high blood pressure like very bad headache or dizziness, passing out, or change in eyesight.
- Redness or irritation of the palms of hands or soles of feet.
- A burning, numbness, or tingling feeling that is not normal.
- Change in eyesight, eye pain, or severe eye irritation.
- Fever, chills, or sore throat; any unexplained bruising or bleeding; or feeling very tired or weak.
- Certain lung problems have happened with this drug. These lung problems could be deadly. Call your doctor right away if you have signs of lung problems like shortness of breath, other trouble breathing, cough that is new or worse, or fever.
All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:
- Hair loss.
- Stomach pain or heartburn.
- Mouth irritation or mouth sores.
- Change in nails.
- Feeling tired or weak.
- Dry skin.
- Dry eyes.
- Back, bone, joint, muscle, or neck pain.
- Weight loss.
- Signs of a common cold.
- Runny or stuffy nose.
- Pimples (acne).
- Skin irritation.
- Diarrhea, throwing up, upset stomach, and decreased appetite are common with this drug. If these happen, talk with your doctor about ways to lower these side effects. Call your doctor right away if any of these effects bother you, do not get better, or are severe.
These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.
You may report side effects to your national health agency.
Use this drug as ordered by your doctor. Read all information given to you. Follow all instructions closely.
- Take with or without food.
- Take this drug at the same time of day.
- Swallow whole. Do not chew, break, open, or dissolve.
- Keep taking this drug as you have been told by your doctor or other health care provider, even if you feel well.
- If you throw up after taking a dose, do not repeat the dose. Take your next dose at your normal time.
- Take a missed dose as soon as you think about it.
- If it has been 6 hours or more since the missed dose, skip the missed dose and go back to your normal time.
- Do not take 2 doses at the same time or extra doses.
- Store at room temperature in a dry place. Do not store in a bathroom.
- Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
- Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.
- If your symptoms or health problems do not get better or if they become worse, call your doctor.
- Do not share your drugs with others and do not take anyone else’s drugs.
- Some drugs may have another patient information leaflet. If you have any questions about this drug, please talk with your doctor, nurse, pharmacist, or other health care provider.
- Some drugs may have another patient information leaflet. Check with your pharmacist. If you have any questions about this drug, please talk with your doctor, nurse, pharmacist, or other health care provider.
- If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.
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