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Lapatinib

Generic Name: Lapatinib (la PA ti nib)
Brand Name: Tykerb

  • Very bad and sometimes deadly liver problems have happened with lapatinib. Call your doctor right away if you have signs of liver problems like dark urine, feeling tired, not hungry, upset stomach or stomach pain, light-colored stools, throwing up, or yellow skin or eyes.

Uses of Lapatinib:

  • It is used to treat breast cancer.

What do I need to tell my doctor BEFORE I take Lapatinib?

  • If you have an allergy to lapatinib or any other part of this medicine.
  • If you are allergic to any drugs like this one, any other drugs, foods, or other substances. Tell your doctor about the allergy and what signs you had, like rash; hives; itching; shortness of breath; wheezing; cough; swelling of face, lips, tongue, or throat; or any other signs.
  • If you have any of these health problems: Low potassium or magnesium levels.
  • If you are breast-feeding or plan to breast-feed.

This is not a list of all drugs or health problems that interact with lapatinib.

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 medicine with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take Lapatinib?

  • Tell all of your health care providers that you take lapatinib. This includes your doctors, nurses, pharmacists, and dentists.
  • If you have upset stomach, throwing up, loose stools (diarrhea), or are not hungry, talk with your doctor. There may be ways to lower these side effects.
  • Loose stools (diarrhea) have happened with this medicine. Sometimes, diarrhea has been very bad and deaths have happened. Talk with your doctor.
  • If you have loose stools (diarrhea), talk with your doctor. Do not try to treat diarrhea without first checking with your doctor.
  • Have blood work checked as you have been told by the doctor. Talk with the doctor.
  • You will need to have heart function tests while taking lapatinib. Talk with the doctor.
  • Avoid grapefruit and grapefruit juice.
  • If you are taking digoxin, talk with your doctor. You may need to have your blood work checked more closely while you are taking it with this medicine.
  • This medicine may cause harm to the unborn baby if you take it while you are pregnant.
  • Use birth control that you can trust to prevent pregnancy while taking lapatinib.
  • If you are pregnant or you get pregnant while taking this medicine, call your doctor right away.

How is this medicine (Lapatinib) best taken?

Use lapatinib as ordered by your doctor. Read all information given to you. Follow all instructions closely.

  • Take on an empty stomach.
  • Take 1 hour before or 1 hour after a meal.
  • To gain the most benefit, do not miss doses.
  • Keep taking this medicine as you have been told by your doctor or other health care provider, even if you feel well.

What do I do if I miss a dose?

  • Skip the missed dose and go back to your normal time.
  • Do not take 2 doses at the same time or extra doses.

See also: Dosage Information (in more detail)

What are some side effects that I need to call my doctor about 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 or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
  • Signs of lung or breathing problems like shortness of breath or other trouble breathing, cough, or fever.
  • Shortness of breath, a big weight gain, or swelling in the arms or legs.
  • A heartbeat that does not feel normal.
  • Chest pain or pressure or a fast heartbeat.
  • Dizziness or passing out.
  • Very bad belly pain.
  • Very upset stomach or throwing up.
  • Loose stools (diarrhea) or loose stools with stomach cramps, upset stomach, throwing up, fever, or fluid loss.
  • Redness or irritation of the palms of hands or soles of feet.
  • A very bad skin reaction (Stevens-Johnson syndrome/toxic epidermal necrolysis) may happen. It can cause very bad health problems that may not go away, and sometimes death. Get medical help right away if you have signs like red, swollen, blistered, or peeling skin (with or without fever); red or irritated eyes; or sores in your mouth, throat, nose, or eyes.

What are some other side effects of Lapatinib?

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:

  • Upset stomach or throwing up.
  • Dry skin.
  • Itching.
  • Headache.
  • Hair loss.
  • Back pain.
  • Nosebleed.
  • Change in finger nails.
  • Mouth irritation or mouth sores.
  • Feeling tired or weak.
  • Not hungry.
  • Not able to sleep.

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 the FDA at 1-800-FDA-1088. You may also report side effects at http://www.fda.gov/medwatch.

See also: Side effects (in more detail)

If OVERDOSE is suspected:

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.

How do I store and/or throw out Lapatinib?

  • Store at room temperature.
  • Store 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.
  • Check with your pharmacist about how to throw out unused drugs.

Consumer Information Use and Disclaimer

  • 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.
  • Keep a list of all your drugs (prescription, natural products, vitamins, OTC) with you. Give this list to your doctor.
  • Talk with the doctor before starting any new drug, including prescription or OTC, natural products, or vitamins.
  • Some drugs may have another patient information leaflet. Check with your pharmacist. If you have any questions about lapatinib, 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.

This information should not be used to decide whether or not to take this medicine or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about lapatinib. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not specific medical advice and does not replace information you receive from the healthcare provider. You must talk with the healthcare provider for complete information about the risks and benefits of using lapatinib.

Review Date: September 6, 2017

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