Lapatinib oral tablet

What is this medication?

LAPATINIB (la PA ti nib) treats breast cancer. It works by slowing down the growth of cancer cells.

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

COMMON BRAND NAME(S): Tykerb

What should I tell my care team before I take this medication?

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

• Heart disease
• Irregular heartbeat or rhythm
• High blood pressure
• Low levels of magnesium in the blood
• Low levels of potassium in the blood
• 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 medication?

Take this medication by mouth. Take it as directed on the prescription label at the same time every day. Do not cut, crush or chew this medication. Swallow the tablets whole. Take it on an empty stomach, at least 1 hour before and 1 hour after food. Keep taking it unless your care team tells you to stop.

Avoid grapefruit juice when taking this medication.

Talk to your care team regarding the use of this medication in children. Special care may be needed.

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, skip it. Take your next dose at the normal time. Do not take extra or 2 doses at the same time to make up for the missed dose.

What may interact with this medication?

Do not take this medicine with any of the following:

• Cisapride
• Dronedarone
• Fluconazole
• Pimozide
• Posaconazole
• Saquinavir
• Thioridazine

This medicine may also interact with the following medications:

• Antiviral medicines for HIV or AIDS
• Certain antibiotics like clarithromycin, erythromycin, and telithromycin
• Certain antibiotics like rifabutin, rifampin, and rifapentine
• Certain medicines for depression, anxiety, or psychotic disturbances
• Certain medicines for fungal infections like itraconazole, ketoconazole, or voriconazole
• Certain medicines for seizures like carbamazepine, phenobarbital, phenytoin
• Dexamethasone
• Digoxin
• Nefazodone
• Other medicines that prolong the QT interval (cause an abnormal heart rhythm) like dofetilide, ziprasidone
• St. John's Wort

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 medication?

This medication may make you feel generally unwell. This is not uncommon as chemotherapy can affect healthy cells as well as cancer cells. Report any side effects. Continue your course of treatment even though you feel ill unless your care team tells you to stop.

Do not become pregnant while taking this medication or for 1 week after stopping it. Women should inform their care team if they wish to become pregnant or think they might be pregnant. Men should not father a child while taking this medicine and for 1 week after stopping it. There is a potential for serious side effects to an unborn child. Talk to your care team for more information. Do not breast-feed an infant while taking this medication or for 1 week after stopping it.

What side effects may I notice from receiving this medication?

Side effects that you should report to your care team as soon as possible:

• Allergic reactions—skin rash, itching, hives, swelling of the face, lips, tongue, or throat
• Diarrhea
• Heart rhythm changes—fast or irregular heartbeat, dizziness, feeling faint or lightheaded, chest pain, trouble breathing
• Liver injury—right upper belly pain, loss of appetite, nausea, light colored stool, dark yellow or brown urine, unusual weakness or fatigue
• Redness, blistering, peeling or loosening of the skin, including inside the mouth
• Swelling of the ankles, hands, or feet
• Trouble breathing

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

• Cough
• Loss of appetite
• Nausea
• Pain, redness, or swelling with sores inside the mouth or throat
• Vomiting

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 medication?

Keep out of the reach of children and pets.

Store at room temperature between 20 and 25 degrees C (68 and 77 degrees F). Get rid of any unused medicine after the expiration date.

To get rid of medications that are no longer needed or have expired:

• Take the medication to a medication take-back program. Check with your pharmacy or law enforcement to find a location.
• If you cannot return the medication, check the label or package insert to see if the medication should be thrown out in the garbage or flushed down the toilet. If you are not sure, ask your care team. If it is safe to put in the trash, take the medication out of the container. Mix the medication with cat litter, dirt, coffee grounds, or other unwanted substance. Seal the mixture in a bag or container. Put it in the trash.

NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.