Other drugs may interact with trastuzumab, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.
Trastuzumab can have long lasting effects on your heart, especially if you receive other cancer medicines. For at least 7 months after your last dose of Herceptin, tell any doctor who treats you that you have used this medicine.
 Herceptin drug interactions (more detail)
