Page last reviewed: 13/07/2011

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 intravenously (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.

The National Institute for Health and Clinical Excellence (NICE) has given its approval for Herceptin to be offered to some people with early and advanced breast cancer.

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 woman in five with breast cancer has a tumour that is 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.

Page last reviewed: 13/07/2011

Some people may experience side effects while taking Herceptin.

Possible side effects include:

  • flu-like symptoms, including a high temperature and aches and pains
  • chest pain
  • diarrhoea
  • stomach pain
  • nausea and vomiting
  • headaches
  • cough and shortness of breath
  • heart damage (reducing the heart's ability to pump blood efficiently)

Very rarely, Herceptin can cause severe allergic reactions, including a rash, itching and breathlessness.

Medicines are available to treat some of the side effects of Herceptin.

Monitoring heart function

Your specialist or healthcare professional will assess your normal heart function before starting treatment with Herceptin, to avoid possible heart problems.

Researchers recommend that women are monitored for signs and symptoms of congestive heart failure or reduced heart function during and after treatment with Herceptin, even if they do not have a history of heart problems.

Content provided by NHS Choices www.nhs.uk and adapted for Ireland by the Health A-Z.

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