Cautions with other medicines
Most medicines do not affect the way trastuzumab works.
It may take over 6 months for trastuzumab to leave your body. Tell your doctor, pharmacist or nurse that you've had trastuzumab if you start any new medicine, even after stopping treatment.
If you need to have any vaccines, speak to your doctor, nurse or pharmacist first. You can have inactivated vaccines such as the flu vaccine or coronavirus (COVID-19) vaccine. If your immune system is weak you need to avoid live vaccines. Ask your doctor, nurse or pharmacist for advice.
Mixing trastuzumab with herbal remedies and supplements
There's not enough information to say that herbal remedies and supplements are safe to take with trastuzumab. They're not tested in the same way as pharmacy and prescription medicines. They're generally not tested for the effect they have on other medicines.
Important: Medicine safety
Tell your doctor or pharmacist if you're taking any other medicines, including herbal remedies, vitamins or supplements.