Lapatinib is an antitumor agent that reversibly blocks tyrosine kinase activity. The drug is available in 250 mg film-coated tablets.

How it works: In breast cancer, the amount of HER2 protein increases in tumor cells, which promotes the growth and division of cancer cells. Lapatinib blocks this protein, slowing down the growth and division of cancer cells, as well as destroying them.

When it is applied

Lapatinib is used to treat adults over the age of 18 with locally advanced or metastatic breast cancer if an increased amount of HER2 protein is found in cancer cells.

The drug is taken in combination with other antitumor agents.:

• with capecitabine if cancer has previously been treated with trastuzumab;
• with trastuzumab if the cancer is not hormone-sensitive and has previously undergone other treatment;
• with aromatase inhibitors if the cancer is hormone-sensitive and has been diagnosed in a postmenopausal woman.

When not to apply

The drug is contraindicated in:

• allergies to lapatinib or other components of the medicine;
• pregnancy and lactation.

With caution, it is prescribed for conditions that can cause heart problems, as well as for moderate or severe renal failure.

How to accept

The dosage depends on which medications lapatinib is used with.:

• together with capecitabine — 1250 mg (5 tablets) per day;
• together with trastuzumab — 1000 mg (4 tablets) per day;
• together with an aromatase inhibitor, 1,500 mg (6 tablets) per day.

The drug is taken once a day, at least an hour before or an hour after a meal.

The course of treatment lasts as long as the doctor prescribes. It can be several months or years.

Possible side effects

Among the side effects:

• digestive disorders: decreased appetite, diarrhea, nausea, vomiting, increased levels of bilirubin and liver enzymes;
• from the heart: decreased contractility of the left ventricle;
• from the lungs: interstitial process or pneumonitis;
• skin: rashes, including acne;
• General condition: weakness.