Herceptin is the brand name of a medicine called trastuzumab. It can stop the growth of breast cancer and sometimes reduce the size of the tumour.
Herceptin is given by a drip into a vein, through a fine tube. It can be given in combination with chemotherapy, or on its own to people who have already had two courses of chemotherapy.
How Herceptin works
Herceptin is only recommended for people who have high levels of HER2 protein. HER2 is found on the surface of some breast cancer cells.
Herceptin attaches itself to the HER2 protein, which prevents a protein called epidermal growth factor reaching the cancer cells. This stops the cancer cells dividing and growing.
Herceptin has little effect on people who do not have high levels of HER2 protein. Around one in five women with breast cancer have tumours that are sensitive to Herceptin. You can have a test to check your levels of HER2 protein if your specialist believes it is appropriate.
Herceptin is not recommended for people with a pre-existing heart condition.
Last updated: 04 October 2011
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