Side-effects with tamoxifen are unusual.
Unwanted effects include:
- vaginal bleeding
- hot flushes - treatment with clonidine has been shown to be effective in reducing tamoxifen associated hot flushes in postmenopausal women with breast cancer (2)
- suppression of menstruation
- gastrointestinal disturbance
- increased bone pain from metastases
- rarely, hypercalcaemia in metastatic disease
- thromboembolism
The incidence of symptomatic endometrial cancer in patients taking tamoxifen is estimated to be less than 20 in 10000 women treated per year.
Reference:
- (1) Bergman, E, Beelen, MLR. et al. (2000). Risk and prognosis of endometrial cancer after tamoxifen for breast cancer. Lancet, 356, 881-7.
- (2) Pandya KJ et al (2000). Oral clonidine in postmenopausal patients with breast cancer experiencing tamoxifen-induced hot flushes: a University of Rochester Cancer Center Community Clinical Oncology Program Study. Ann Intern Med, 132, 788-93.