About tucatinib
HER2-targeted tyrosine kinase inhibitor
Used for
- HER2-positive advanced breast cancer, with trastuzumab and capecitabine.
- HER2-positive colorectal cancer that has spread, with trastuzumab, after prior treatment.
Usual adult dose
300 mg by mouth twice daily with trastuzumab and capecitabine; reduce for side effects or liver problems.
Common side effects
- Diarrhea
- Rash
- Nausea and vomiting
- Liver enzyme increases
Important warnings
- Can cause serious diarrhea; severe cases may require treatment interruption.
- May cause serious liver injury; liver tests are monitored during treatment.
- Can harm an unborn baby; effective contraception is recommended during treatment and for one week afterward.
- Tablets should be swallowed whole; do not crush, chew, or split.
Pregnancy
May cause fetal harm. Avoid pregnancy during treatment and for at least one week after the last dose.
Breastfeeding
Do not breastfeed during treatment and for one week after the last dose.
Interactions
- Strong or moderate CYP2C8 inhibitors can increase tucatinib levels.
- Strong CYP3A or moderate CYP2C8 inducers can reduce tucatinib levels.
- Tucatinib can raise levels of CYP3A or P-glycoprotein substrate medicines.
AI-generated from general medical knowledge, not from this product's official leaflet. It may be incomplete or out of date. Not medical advice — ask a pharmacist or doctor before making any decision.