The benefits are greater where the tumour is oestrogen receptor positive. For women who have been through the menopause there is some evidence to suggest that tamoxifen slows down the process of bone loss, so reducing the risk of osteoporosis. It may lower the risk of heart disease by reducing the levels of cholesterol in the blood. Like any drug, tamoxifen can have side effects. However, everyone reacts differently to drugs.
Some people have more side effects than others, and some people have no side effects at all.
Some side effects are mentioned below, but if you experience any new symptoms it is important to discuss them with your GP, specialist or breast care nurse. The most common side effects are similar to menopausal symptoms, such as hot flushes. Some women may have indigestion or mild nausea, although these symptoms usually improve with time. Women who are still having regular periods may find that they become less regular, lighter or stop completely. Other possible side effects include headaches, vaginal irritation or discharge and leg cramps at night.