Uses of Medicine:
Lapatinib, supplied generically under the brand Hertab is a type of medication called a kinase inhibitor. It is used alongside:
- Capecitabine to treat patients with advanced or metastatic breast cancer whose tumors have too much of the HER2 protein and who have already been treated with other therapies, including anthracyclines, taxanes, and trastuzumab.
- Letrozole for postmenopausal women with hormone receptor-positive metastatic breast cancer that also overexpresses the HER2 protein, and who are suitable for hormonal therapy.
Dosage & Side Effects:
For advanced or metastatic breast cancer, the recommended dosage of Lapatinib is 1,250 mg (5 tablets) once daily for 21 days, combined with capecitabine 2,000 mg/m²/day (split into 2 doses about 12 hours apart) for 14 days in a 21-day cycle.
For hormone receptor-positive, HER2-positive metastatic breast cancer, Lapatinib should be taken at 1,500 mg (6 tablets) once daily with letrozole 2.5 mg once daily. Take Lapatinib at least 1 hour before or after a meal, and take capecitabine with food or within 30 minutes after eating. Do not split the daily dose of Lapatinib.
When taking Lapatinib with capecitabine, the most frequently occurring side effects (affecting more than 20% of patients) include diarrhea, palmar-plantar erythrodysesthesia (a skin condition affecting the hands and feet), nausea, rash, vomiting, and fatigue. On the other hand, when Lapatinib is used with letrozole, the most common side effects (affecting 20% or more of patients) are diarrhea, rash, nausea, and fatigue.
