I was on tamoxifen for seven months but found the side effects difficult. Tamoxifen caused severe leg cramping, menopausal symptoms (I am post-menopausal), abdominal discomfort, and depression. I began to fear endometrial thickening and leg thrombosis. My oncologist switched me to Arimidex/anastrazole, which I have been taking since March with very slight SE's. With anastrazole (Accord brand) I get some occasional slight nighttime foot cramping. Both hormone blockers seem to cause hot flashes and increase insomnia. I experience no muscular aches and pains from the anastrazole. I take the pill in the morning with breakfast, followed by a walk, and that followed three days a week by weight training and yoga practice at the gym. I am hoping a good plant-based diet, exercise, and normal BMI, in addition to this little pill, keep me healthy and breast cancer recurrence free. No guarantees with any of these pills.