Lapatinib Oral tablet

What is this medicine?

LAPATINIB (la PA ti nib) is a chemotherapy drug. It targets specific enzymes within cancer cells and stops the cancer cells from growing. This medicine is used to treat some advanced breast cancers. It is often used along with other cancer treatments.

This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.

What should I tell my health care provider before I take this medicine?

They need to know if you have any of these conditions:

  • heart disease

  • heart rhythm problems (irregular heartbeat)

  • high blood pressure

  • history of low levels of potassium or magnesium

  • liver disease

  • an unusual reaction to lapatinib, other medicines, foods, dyes, or preservatives

  • pregnant or trying to get pregnant

  • breast-feeding

How should I use this medicine?

Take this medicine by mouth with a glass of water. Take this medicine on an empty stomach, at least 1 hour before or after a meal. Do not take with food. Follow the directions on the prescription label. Do not take your medicine more often than directed. Do not stop taking except on your doctor's advice.

Talk to your pediatrician regarding the use of this medicine in children. Special care may be needed. This medicine is not approved for use in children.

Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.

NOTE: This medicine is only for you. Do not share this medicine with others.

What if I miss a dose?

If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.

What may interact with this medicine?

Do not take this medicine with any of the following:

  • certain medicines for fungal infections like fluconazole, itraconazole, ketoconazole, posaconazole, voriconazole

  • cisapride

  • dofetilide

  • dronedarone

  • grapefruit or grapefruit juice

  • pimozide

  • thioridazine

  • ziprasidone

This medicine may also interact with the following medications:

  • antiviral medicines for HIV or AIDS

  • certain antibiotics like clarithromycin, erythromycin, rifabutin, rifampin, rifapentine, telithromycin

  • certain medicines for depression, anxiety, or psychotic disturbances

  • certain medicines for irregular heart beat

  • certain medicines for seizures like carbamazepine, phenobarbital, phenytoin

  • certain medicines for stomach problems like cimetidine, famotidine, ranitidine, omeprazole

  • cyclosporine

  • daunorubicin

  • dexamethasone

  • diltiazem

  • doxorubicin

  • other medicines that prolong the QT interval (cause an abnormal heart rhythm)

  • St. John's Wort or other herbal supplements

  • verapamil

This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.

What should I watch for while using this medicine?

Visit your doctor for checks on your progress. You will need to have regular blood tests while on this medicine.

Report any new symptoms promptly. Let your doctor know if you have any change in bowel patterns, nausea, loss of appetite, or vomiting, as these side effects may cause dehydration. If you have shortness of breath, contact your doctor. Possible serious side effects include heart or lung problems.

Do not become pregnant while taking this medicine. Women should inform their doctor if they wish to become pregnant or think they might be pregnant. There is a potential for serious side effects to an unborn child. Talk to your health care professional or pharmacist for more information. Do not breast-feed an infant while taking this medicine.

What side effects may I notice from receiving this medicine?

Side effects that you should report to your doctor or health care professional as soon as possible:

  • allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue

  • breathing problems

  • chest pain

  • cough that does not go away

  • dizziness

  • feeling faint or lightheaded, falls

  • fever or chills, sore throat

  • palpitations

  • severe or persistent diarrhea

  • swelling of feet, legs

  • unusual bleeding, bruising

  • vomiting

  • yellowing of the eyes or skin

Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):

  • decreased appetite

  • diarrhea

  • dry skin

  • heartburn

  • mouth sores

  • nausea

  • red, numb, swollen, or painful hands or feet

  • stomach upset

  • tired

This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Where should I keep my medicine?

Keep out of the reach of children.

Store at room temperature between 15 and 30 degrees C (59 and 86 degrees F). Protect from moisture. Keep tightly closed. Throw away any unused medicine after the expiration date.