In which cases is it absolutely contraindicated or necessary to use Tucatinib with caution?

In which cases is it absolutely contraindicated or necessary to use Tucatinib with caution?

First, if you are allergic to tucatinib or any other ingredients in tucatinib tablets (such as copovidone, crospovidone, sodium chloride, potassium chloride, etc.), you must not take this medicine. Second, before taking the medicine, you must inform your doctor if you have any liver problems. During treatment, your doctor will closely monitor your liver function and determine whether you are suitable to continue taking the medicine based on the results. Additionally, tucatinib may cause severe diarrhea, a side effect that requires high vigilance. At the first sign of diarrhea such as loose stools, or if diarrhea persists and is accompanied by nausea or vomiting, you must contact your doctor immediately to avoid more serious health problems caused by significant loss of fluids and electrolytes.

Warnings for use in children, pregnant women, and breastfeeding women

Tucatinib is not intended for use in children and adolescents under 18 years of age, as its safety and efficacy have not been established in this age group. For pregnant women, this medicine may cause harm to an unborn baby. Therefore, women of childbearing potential must have a pregnancy test before starting treatment, and must use effective contraception during treatment and for at least 1 week after the last dose. If you become pregnant during treatment, tell your doctor immediately. Male patients with a female partner of childbearing potential should also use contraception during treatment and for 1 week after stopping treatment. Moreover, it is unknown whether tucatinib passes into breast milk. To be safe, you should not breastfeed during treatment and for at least 1 week after the last dose, and consult your doctor about alternative feeding methods.

Potential interactions of tucatinib with other drugs

Certain drugs may affect the concentration or efficacy of tucatinib in the body, and vice versa. Therefore, patients must inform their doctor of all medications they are taking, including prescription drugs, over-the-counter drugs, and herbal products. Drug classes requiring special attention include: St. John's wort (a herbal product used for depression); antifungal drugs (e.g., itraconazole, ketoconazole); the antibiotic rifampin; anti-HIV drugs (e.g., darunavir); anti-seizure drugs (e.g., phenytoin, carbamazepine); and various drugs used to lower cholesterol, relieve pain, treat diabetes, control immune rejection, etc. Your doctor will determine whether dose adjustments or medication changes are needed to avoid potential drug interactions.