Tamoxifen citrate is an oral medication approved by the Food and Drug Administration. It has been used for over thirty years to treat breast cancer in both women and men, according to the National Cancer Institute (NCI). This drug is known as a selective estrogen receptor modulator (SERM); specifically, it blocks the female hormone, estrogen, from acting on breast cells in breast cancers that are hormone receptive or hormone positive.
Gastrointestinal
Various types of stomach problems are associated with Tamoxifen, which are not considered serious. These include nausea and vomiting, indigestion or an upset stomach.
Hot Flashes
Some of the most common reported side effects are menopausal symptoms such as hot flashes, irregular menstrual periods, vaginal discharge or vaginal dryness and mood changes. These symptoms are not considered serious, and they vary depending on the person.
Circulatory
According to the NCI, the Breast Cancer Prevention Trial found that being on Tamoxifen for several years slightly increases the risk for blood clots, pulmonary emboli and strokes. Changes in terms of easy bruising or bleeding also may result. This effect is prominent when Tamoxifen is combined with chemotherapy. Thus, it is contraindicated to treat individuals with Tamoxifen who have a history of blood clots or other circulatory problems.
Malignancy
There are potentially serious side effects of taking this drug. Tamoxifen stimulates estrogen in the lining of the uterus. According to the NCI, women who take Tamoxifen are at increased risk for two types of uterine malignancy: endometrial (uterine lining) and uterine sarcoma (uterine wall). The risk is considered small, and the benefits of this drug are usually considered to outweigh this potential outcome.
