Tamoxifen usage in premenopausal women causes their estrogen levels to increase significantly, and may be associated with heavier periods. Ovarian function does not seem to be surpressed due to the antiestrogenic properties of tamoxifen. Adjuvant chemotherapy that affects ovarian function with or without tamoxifen treatment can cause premature menopause. During the perimenopausal period, a biological span that could last for 5 years or more, a woman may experience menstrual irregularities regardless of the therapy used. Epidemiological studies of populations using tamoxifen as therapy have failed to find an increase in depressive episodes, while other studies reported an increased incidence of depression.
Depression is a real, but uncommon side effect of tamoxifen.
Women using tamoxifen should be screened regularly for symptoms of depression and treated appropriately. An occasional reduction in dosage may be necessary to control symptoms. Tamoxifen has recently been proposed for the use in prevention of breast cancer, as well. The ideal length of therapy and whether or not to start therapy as a high-risk woman should be discussed with your doctor and be based on your individual factors. University of Pennsylvania, a National Center of Excellence in Women's Health sponsored by the Office on Women's Health in the Department of Health and Human Services.