Tamoxifen for breast cancer in women
Tamoxifen is a drug that stops oestrogen from attaching to breast cancer cells and encouraging them to grow. It is occasionally used in post-menopausal women. Some women take it for a few years and then go on to take an aromatase inhibitor.
Doctors sometimes prescribe tamoxifen if you have problems with your bones or troublesome side effects with AIs. Tamoxifen doesn’t cause bone thinning in post-menopausal women, but it can slightly increase the risk of womb cancer. It’s important to tell your doctor if you have any vaginal bleeding.
Tamoxifen is the main hormonal therapy for women who have not been through menopause. It’s taken daily as a tablet.
The side effects are similar to the effects of the menopause and may include:
Tamoxifen can slightly increase your risk of a blood clot.
You’ll usually have tamoxifen for at least five years. But recent trial results show that taking it for 10 years can reduce the risk of the cancer coming back further. You can talk to your doctor about this. It won’t be suitable for everyone, especially if you have side effects or want to have children. If you’re close to your natural menopause when you start tamoxifen, your doctor may change your treatment to an aromatase inhibitor after a few years.
We have more detailed information on tamoxifen, including how it works, how it’s taken and the side effects it may cause.