What are the common side effects of lapatinib/telisa

Lapatinib(Lapatinib) is a dual-target tyrosine kinase inhibitor that acts on HER2 and EGFR. Like most targeted drugs, its side effects are closely related to the drug's mechanism of action, mainly manifesting as gastrointestinal reactions, skin reactions, and changes in liver function. Since lapatinib can inhibit the normal activity of cell signaling pathways and some normal cells will also be affected, the patient's physiological indicators need to be monitored regularly during treatment.

Clinically, the most common adverse reactions include diarrhea, nausea, decreased appetite and mild fatigue. Such symptoms usually appear at the beginning of medication and will be relieved as the body adapts or the dose is adjusted. Diarrhea is one of the most common side effects of lapatinib. The reason is that the drug's inhibition of the EGFR pathway in intestinal epithelial cells leads to temporary disturbance of absorption function. Doctors usually advise patients to increase fluid intake and, if necessary, use antidiarrheal drugs to control symptoms.

Skin adverse reactions are mostly manifested as rash, dryness and itching, which is related to EGFR signal inhibition leading to affected keratinocyte differentiation. Most patients only have mild reactions, which can be improved by moisturizing or topical anti-inflammatory treatment. Relatively rare but serious adverse events include liver function damage and cardiotoxicity. Especially patients with a history of previous heart disease or combined use of other cardiotoxic drugs need to closely monitor electrocardiogram and liver function indicators.

In addition, some patients may experience hand-foot syndrome or alopecia while taking the drug, but most of these adverse reactions are reversible. It is worth noting that the drug metabolism of lapatinib depends on the liver CYP3A4 enzyme system. Therefore, when used together with other drugs metabolized through this pathway, it may cause drug interactions, and doctors need to adjust the dose according to the situation.

Reference materials:https://medlineplus.gov/druginfo/meds/a607055.html