Tamoxifen - Breast Cancer treatment
Tamoxifen is a widely used drug often prescribed to women with a type of breast cancer that feeds off the hormone oestrogen. It can be used to reduce the risk of the cancer occurring in the other breast or spreading to other parts of the body (metastatic breast cancer). Tamoxifen also has a preventive role and in certain cases has been prescribed to women regarded as having a high risk of developing breast cancer.
The drug, which has the brand name Novaldex, is an extremely weak version of oestrogen. It works by interfering with the body’s much more powerful natural oestrogen which fuels the growth of cancerous cells. In effect these “oestrogen-receptive cells” are tricked by the tamoxifen into remaining dormant and after a period of time they may literally starve to death.
The drug can be taken either as a pill or liquid and a course of treatment commonly lasts five years following the initial treatment for breast cancer.
Tamoxifen Side Effects
Common side effects include menopausal-type hot flushes which in some cases are so severe that women have been forced to abandon the drug. As one woman put it: “It feels as if someone’s stoking a boiler inside me. It’s so bad my glasses steam up!”
Fatigue, weight gain, nausea and vaginal discomfort and dryness are other common problems reported by women on tamoxifen. More serious and potentially life-threatening complications include blood clots on the lung (pulmonary emboli), eye damage and cancer of the uterus. It may seem ironic that a drug used to prevent one type of cancer can actually cause another but in 1996 the World Health Organization (WHO) officially declared tamoxifen a known carcinogen (cancer-causing agent).
It’s important to understand and weigh up the benefits and risks of tamoxifen before committing yourself to a course of treatment. Some of the side effects described here may lessen or disappear after a few weeks; others may continue and be so unpleasant that they make continued use of the drug intolerable.
Women who are pre-menopausal and taking tamoxifen should be careful to use contraception because even if the drug upsets the normal pattern of your periods, pregnancy is still possible. In fact some studies have shown that tamoxifen can actually boost a woman’s fertility. Avoid oestrogen-based contraceptive pills in favor of condoms, the coil or diaphragm.
If you’re planning a pregnancy you should stop taking the drug for at least a couple of months before conception. There have been no recorded cases of tamoxifen damaging an unborn child but it’s wise to allow sufficient time for your body to be completely clear of the drug to avoid any possible.