How does trastuzumab work?
Trastuzumab binds to HER2 receptors on cancer cells, blocking their ability to grow and divide. It can also stimulate the immune system to help destroy cancer cells.
What is trastuzumab used to treat?
Trastuzumab is commonly prescribed for:
- HER2-positive breast cancer (early and advanced/metastatic stages)
- HER2-positive gastric (stomach) cancer
Who can take trastuzumab?
Trastuzumab is suitable for most adults with HER2-positive cancers, as prescribed by an oncologist.
Who might not be able to take trastuzumab?
Trastuzumab may not be suitable if you:
- Have severe heart disease or heart failure
- Have had a severe allergic reaction to trastuzumab or similar treatments
- Are pregnant or planning to conceive
Can I take trastuzumab if I’m pregnant or breastfeeding?
Trastuzumab isn’t recommended during pregnancy, as it may harm the baby. If you are breastfeeding, speak to your doctor, as it is unknown if trastuzumab passes into breast milk.
What if I miss a dose?
If you miss a dose, contact your doctor or treatment team as soon as possible to discuss the next steps.
How effective is trastuzumab?
Trastuzumab is highly effective at improving survival rates and reducing tumour growth in HER2-positive cancers when used as part of a treatment plan.
What should I do if I take too much?
Trastuzumab is given in a controlled setting by a healthcare professional, but if an overdose is suspected, seek immediate medical attention.
What dose of trastuzumab is usually taken?
- For early and metastatic breast cancer: Loading dose of 8mg/kg, followed by 6mg/kg every three weeks (or as prescribed by your doctor).
- For gastric cancer: Similar dosing based on weight and treatment plan.
Your doctor will determine the correct dose based on your condition and treatment plan.
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What are the side effects of trastuzumab?
Common side effects include:
- Flu-like symptoms (fever, chills, fatigue)
- Nausea or diarrhoea
- Heart problems (such as reduced heart function or heart failure)
- Injection site reactions (if given as a subcutaneous injection)
Serious side effects, such as shortness of breath, chest pain, or severe allergic reactions, require urgent medical attention.
How should I take trastuzumab?
Trastuzumab is administered as an intravenous (IV) infusion or subcutaneous injection in a hospital or clinic setting.
When should trastuzumab be taken?
Trastuzumab is usually given every one to three weeks, as part of a structured treatment plan.
What are the brand names for trastuzumab?
Trastuzumab is available as a generic medicine, but some branded versions include:
- Herceptin
- Ontruzant
- Kanjinti
- Trazimera
Final thoughts
Trastuzumab is an effective targeted therapy for HER2-positive cancers, but it should be taken exactly as prescribed. Regular heart monitoring may be required during treatment. If side effects occur, speak to your doctor or treatment team.
